Getting a 404 Not found on new site

I am using Ubuntu Minimal. I tried migrating two sites from older server and kept getting a 404 error. I removed the sites and the stack.

Reinstalled the stack, and a demo site. When I try to access the site using I still get a 404 not found error.

Anything I may have gotten wrong.

PS: I have also modified the /etc/hosts file to include

It already had some IPv6 related entries.

Update: I deleted the old server, created a new one, removed the IPv6, but still get the same error. Help please!!