Unable to initialise sdl2 - c++

Question

Im trying to check if sdl is properly installed on my Ubuntu 20.04 and its not.
Running all on 64bit type.
This is my code:
#include <iostream>
#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>
#include <SDL2/SDL_timer.h>
bool initSDL()
{
if (SDL_Init(SDL_INIT_EVERYTHING) != 0)
{
std::cout << "Failed to init sdl: " << SDL_GetError() << std::endl;
return false;
}
if (IMG_Init(IMG_INIT_PNG) != IMG_INIT_PNG)
{
std::cout << "Failed to init sdl_image: " << IMG_GetError() << std::endl;
return false;
}
return true;
}
int main(int argc, char *argv[])
{
std::cout << "Code Starting..." << std::endl;
initSDL();
int winX = 900, winY = 600;
std::cout << "Code Exited Properly." << std::endl;
return 0;
}
And this is my output:
Code Starting...
Failed to init sdl: No available video device
Code Exited Properly.
Im running my code with this commands:
gcc -c src/*.cpp -I include -m64 -lstdc++ -std=c++11
gcc *.o -o out/main -lSDL2main -lSDL2 -lSDL2_image -m64 -lstdc++ -std=c++11
./out/main
My code strucure is this way:
Main directory 'sdl_hello_world'
->src -> contains 'main.cpp'
->out -> contains compiled 'main'
Some methods i tried was:
export DISPLAY=:0
export SDL_VIDEODRIVER=x11
So how do i fix this ?
EDIT: I also followed this tutorial (https://www.youtube.com/watch?v=P3_xhDIP7bc&list=PLvv0ScY6vfd-p1gSnbQhY7vMe2rng0IL0&ab_channel=MikeShah), and still it gave the same error. So i guess the problem is in some computer setting.
EDIT: SOLVED:
i followed almost all tutorials and fix methods on the internet to solve my issue which uses gcc in linux. Some solutions on stack overflow seemed to prefer to compile the source code on their own computer WHICH WORKED.
So im pretty sure the way ubuntu installs it on my computer/ idk im new to using sdl. Updating this as might come handy to anyone else.
Still curious, is there a chance i did something wrong, or could this be considered a bug ?
EDIT: followed this btw https://wiki.libsdl.org/Installation