Alternate name for localhost not working

I tried using an alternate name for localhost.

127.0.0.1   localhost test.dev

This doesn't show apache2 page when I use test.dev but works when I type localhost.
Also I tired using

127.0.0.1   localhost test

This worked with http but not with https, can anyone help?

If you are working locally, you most certainly can point any domain to your localhost within /etc/hosts. I do this all the time for development. What you will want to do, however, is put each domain on its own line.

For example, your /etc/hosts file might look something like this:

127.0.0.1       localhost
127.0.0.1       test.dev
127.0.0.1       another.dev
127.0.0.1       yet.another.dev

The .dev addresses above would all be handled by the local web server.

Where this can fall down, though, is when you're using a browser that wants to use its own DNS mechanisms. When this happens, it doesn't matter what you have in /etc/hosts, because the browser will ask an external DNS provider directly and cache the result.

If you would like to avoid TLDs that exist, note that .app is a valid TLD as per Wikipedia, and .devel is certainly free to use. I generally stick to .local for things on my local machine, .vbox for VirtualBox resources, and .{environment} when testing against specific environments (Docker, EC2, etc.). That said, there is nothing stopping you from using a .com in /etc/hosts if you choose ... aside from your browser.