Trouble setting ubuntu vhost file

Trouble setting ubuntu vhost file

Ok. I'm trying to set my config files in ubuntu.
When I look in the sites-available folder, I see
000-default.conf ssl-default.conf
I have a site testsite.com that I need to configure the vhost for https
1) Can I just add a new vhost section to ssl-default.conf? Should I copy
the entire file to testsite.conf and make my edits there? 2) Where should
I put the set up for port 80? 000-default.conf? if I copy the file, do I
need to add the 000 to the file name so that it is read first? 3) where
can I put the info that used to be in the default file ie( allow
overrides, etc)
Thank you