Exposing a web application to the global network using Kubernetes - amazon-web-services

Question

i'm new to K8S, trying some exercises for the first time.
i'm trying to expose a simple web app (nginx) to the outer network. i'm working on an EC2 instance, with elastic ip (for a static ip address).
my deployment.yml file looks like this:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 1
selector:
matchLabels:
app: nginx-deployment
template:
metadata:
labels:
app: nginx-deployment
spec:
containers:
- image: "nginx:latest"
name: nginx
ports:
- containerPort: 80
after running the commands:
kubectl apply -f deployment.yml
kubectl expose deployment nginx-deployment --name my-service --port 8080 --target-port=80 --type=NodePort
i would expect that i could address this simple app by the elastic ip:port (in my situation - 8080). can't connect.
i've tried to see details about my app via the command:
kubectl get services my-service
and got this:
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
my-service NodePort 10.99.98.56 <none> 8080:32725/TCP 26m
i've also tried to open ALL OF THE PORTS in my instance - to check if there's any connection. what i did manage to do is to retrieve the internal ip address with:
kubectl get nodes -o wide
and then by adding the port number (the 32725) with the curl command - i've managed to get the nginx base html page.
my question is this: why couldn't i get the nginx base page via the elastic ip?
and how can i access my simple app?