Drupal 8.5.4 all links give 404 Not Found - drupal-8

Question

I am using Ubuntu 18.04 server and Drupal 8.5.4. The installation was successful.I can login and my home page is displayed . But any other url on the page gives error. One such error is
*
Not Found
The requested URL /drupal-8.5.4/admin/content was not found on this server.
*
Thank you all in anticipation.
These ar all the details I could think of adding. Please let me know if anything else will be required
My .htaccess file is as follows
#
# Apache/PHP/Drupal settings:
#
# Protect files and directories from prying eyes.
<FilesMatch "\.(engine|inc|install|make|module|profile|po|sh|.*sql|theme|twig|tpl(\.php)?|xtmpl|yml)(~|\.sw[op]|\.bak|\.orig|\.save)?$|^(\.(?!well-known).*|Entries.*|Repository|Root|Tag|Template|composer\.(json|lock))$|^#.*#$|\.php(~|\.sw[op]|\.bak|\.orig|\.save)$">
<IfModule mod_authz_core.c>
Require all denied
</IfModule>
<IfModule !mod_authz_core.c>
Order allow,deny
</IfModule>
</FilesMatch>
# Don't show directory listings for URLs which map to a directory.
Options -Indexes
# Set the default handler.
DirectoryIndex index.php index.html index.htm
# Add correct encoding for SVGZ.
AddType image/svg+xml svg svgz
AddEncoding gzip svgz
# Most of the following PHP settings cannot be changed at runtime. See
# sites/default/default.settings.php and
# Drupal\Core\DrupalKernel::bootEnvironment() for settings that can be
# changed at runtime.
# PHP 5, Apache 1 and 2.
<IfModule mod_php5.c>
php_value assert.active 0
php_flag session.auto_start off
php_value mbstring.http_input pass
php_value mbstring.http_output pass
php_flag mbstring.encoding_translation off
# PHP 5.6 has deprecated $HTTP_RAW_POST_DATA and produces warnings if this is
# not set.
php_value always_populate_raw_post_data -1
</IfModule>
# Requires mod_expires to be enabled.
<IfModule mod_expires.c>
# Enable expirations.
ExpiresActive On
# Cache all files for 2 weeks after access (A).
ExpiresDefault A1209600
<FilesMatch \.php$>
# Do not allow PHP scripts to be cached unless they explicitly send cache
# headers themselves. Otherwise all scripts would have to overwrite the
# headers set by mod_expires if they want another caching behavior. This may
# fail if an error occurs early in the bootstrap process, and it may cause
# problems if a non-Drupal PHP file is installed in a subdirectory.
ExpiresActive Off
</FilesMatch>
</IfModule>
# Set a fallback resource if mod_rewrite is not enabled. This allows Drupal to
# work without clean URLs. This requires Apache version >= 2.2.16. If Drupal is
# not accessed by the top level URL (i.e.: http://example.com/drupal/ instead of
# http://example.com/), the path to index.php will need to be adjusted.
<IfModule !mod_rewrite.c>
FallbackResource /index.php
</IfModule>
# Various rewrite rules.
<IfModule mod_rewrite.c>
RewriteEngine on
# Set "protossl" to "s" if we were accessed via https://. This is used later
# if you enable "www." stripping or enforcement, in order to ensure that
# you don't bounce between http and https.
RewriteRule ^ - [E=protossl]
RewriteCond %{HTTPS} on
RewriteRule ^ - [E=protossl:s]
# Make sure Authorization HTTP header is available to PHP
# even when running as CGI or FastCGI.
RewriteRule ^ - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
# Block access to "hidden" directories whose names begin with a period. This
# includes directories used by version control systems such as Subversion or
# Git to store control files. Files whose names begin with a period, as well
# as the control files used by CVS, are protected by the FilesMatch directive
# above.
#
# NOTE: This only works when mod_rewrite is loaded. Without mod_rewrite, it is
# not possible to block access to entire directories from .htaccess because
# <DirectoryMatch> is not allowed here.
#
# If you do not have mod_rewrite installed, you should remove these
# directories from your webroot or otherwise protect them from being
# downloaded.
RewriteRule "/\.|^\.(?!well-known/)" - [F]
# If your site can be accessed both with and without the 'www.' prefix, you
# can use one of the following settings to redirect users to your preferred
# URL, either WITH or WITHOUT the 'www.' prefix. Choose ONLY one option:
#
# To redirect all users to access the site WITH the 'www.' prefix,
# (http://example.com/foo will be redirected to http://www.example.com/foo)
# uncomment the following:
# RewriteCond %{HTTP_HOST} .
# RewriteCond %{HTTP_HOST} !^www\. [NC]
# RewriteRule ^ http%{ENV:protossl}://www.%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
#
# To redirect all users to access the site WITHOUT the 'www.' prefix,
# (http://www.example.com/foo will be redirected to http://example.com/foo)
# uncomment the following:
# RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
# RewriteRule ^ http%{ENV:protossl}://%1%{REQUEST_URI} [L,R=301]
# Modify the RewriteBase if you are using Drupal in a subdirectory or in a
# VirtualDocumentRoot and the rewrite rules are not working properly.
# For example if your site is at http://example.com/drupal uncomment and
# modify the following line:
# RewriteBase /drupal
#
# If your site is running in a VirtualDocumentRoot at http://example.com/,
# uncomment the following line:
# RewriteBase /
# Redirect common PHP files to their new locations.
RewriteCond %{REQUEST_URI} ^(.*)?/(install.php) [OR]
RewriteCond %{REQUEST_URI} ^(.*)?/(rebuild.php)
RewriteCond %{REQUEST_URI} !core
RewriteRule ^ %1/core/%2 [L,QSA,R=301]
# Rewrite install.php during installation to see if mod_rewrite is working
RewriteRule ^core/install.php core/install.php?rewrite=ok [QSA,L]
# Pass all requests not referring directly to files in the filesystem to
# index.php.
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !=/favicon.ico
RewriteRule ^ index.php [L]
# For security reasons, deny access to other PHP files on public sites.
# Note: The following URI conditions are not anchored at the start (^),
# because Drupal may be located in a subdirectory. To further improve
# security, you can replace '!/' with '!^/'.
# Allow access to PHP files in /core (like authorize.php or install.php):
RewriteCond %{REQUEST_URI} !/core/[^/]*\.php$
# Allow access to test-specific PHP files:
RewriteCond %{REQUEST_URI} !/core/modules/system/tests/https?.php
# Allow access to Statistics module's custom front controller.
# Copy and adapt this rule to directly execute PHP files in contributed or
# custom modules or to run another PHP application in the same directory.
RewriteCond %{REQUEST_URI} !/core/modules/statistics/statistics.php$
# Deny access to any other PHP files that do not match the rules above.
# Specifically, disallow autoload.php from being served directly.
RewriteRule "^(.+/.*|autoload)\.php($|/)" - [F]
# Rules to correctly serve gzip compressed CSS and JS files.
# Requires both mod_rewrite and mod_headers to be enabled.
<IfModule mod_headers.c>
# Serve gzip compressed CSS files if they exist and the client accepts gzip.
RewriteCond %{HTTP:Accept-encoding} gzip
RewriteCond %{REQUEST_FILENAME}\.gz -s
RewriteRule ^(.*)\.css $1\.css\.gz [QSA]
# Serve gzip compressed JS files if they exist and the client accepts gzip.
RewriteCond %{HTTP:Accept-encoding} gzip
RewriteCond %{REQUEST_FILENAME}\.gz -s
RewriteRule ^(.*)\.js $1\.js\.gz [QSA]
# Serve correct content types, and prevent mod_deflate double gzip.
RewriteRule \.css\.gz$ - [T=text/css,E=no-gzip:1]
RewriteRule \.js\.gz$ - [T=text/javascript,E=no-gzip:1]
<FilesMatch "(\.js\.gz|\.css\.gz)$">
# Serve correct encoding type.
Header set Content-Encoding gzip
# Force proxies to cache gzipped & non-gzipped css/js files separately.
Header append Vary Accept-Encoding
</FilesMatch>
</IfModule>
</IfModule>
# Various header fixes.
<IfModule mod_headers.c>
# Disable content sniffing, since it's an attack vector.
Header always set X-Content-Type-Options nosniff
# Disable Proxy header, since it's an attack vector.
RequestHeader unset Proxy
</IfModule>
# RewriteBase /~name

Answer 1

Now, Need to activate mod_rewrite:
sudo a2enmod rewrite
This will activate the module or alert you that the module is already in effect. To put these changes into effect, restart Apache:
sudo service apache2 restart

Answer 2

I changed
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
Require all granted
to
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride All
Require all granted
in /etc/apache2/apach2.conf , restarted Apache with service apache2 restart

Answer 3

There are two things
1: Ensure that mod_rewrite is enabled
To check this create a file called phpinfo.php in the root of your site. This file should be accessible from a web browser and contain this code:
phpinfo();
Navigate to phpinfo.php in a browser like this: http://www.example.com/phpinfo.php
On that page, look for a section called "Loaded Modules" and check that mod_rewrite is included. If not, mod_rewrite is not being loaded by apache and will need to be enabled. To enable this mode just write the following command in terminal and restart the apache
sudo a2enmod rewrite
2:Ensure that Drupal's .htaccess file is being used
Once it's been confirmed that mod_rewrite is enabled, double check that Drupal's .htaccess file is in the site's root, and that it is working. Confirm that .htaccess is enabled by temporarily replacing Drupal's .htaccess file. Make a backup of the existing .htaccess and create one like this
DirectoryIndex phpinfo.php
Now try the site URL without specifing a page or file in a web browser: http://www.example.com/. If you see PHP's phpinfo dump, the .htaccess file worked and you can restore the old one. If not, the server may not be allowing .htaccess overrides for your site.To allow this edit you virtual hosting file or apache2.conf file. For apache2.conf file change
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
to
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride All
Restart the apache and hopefully site works well

Answer 4

If you are installing drupal with composer run the composer create-project command at a path where sudo permission is not required and then move the drupal project directory to the apache web server's Document root (i.e /var/www/html which is the default one)
Reason for doing this:
When you run the composer create-project command with sudo, the .htaccess file is not created inside the project directory which causes disabling of all urls except the home page of drupal site
This was a problem due to .htaccess which got solve but if it's because of someother reason check out the documentation or the Drupal forum