why cannot I edit my `hosts` file?

I'm trying to edit my hosts file, because doing ssh <some host in hosts> fails to translate to ip.

according to the Finder UI it is found under:

however when trying to run cat hosts from the terminal I get an error:

➜  /etc  cat hosts
cat: hosts: No such file or directory

I tried to create a new hosts file but then I see another one is created next to the first one

but when I try to edit the second hosts I need to duplicate to anther destination. I copy it to /etc and again the first problem occurs.

I have tried to change the permissions to everyone can read and write. But yet it didn't help.