During install I received a message/warning that I needed to fix /etc/hosts to add ip hostname fqdn etc

I am unsure exactly what I am supposed to edit my hosts file too because it seems like the install example says something like
ipaddress fqdn hostname

I am confused because there is no field for fqdn if you use the gui to edit hosts. instead it offers the fields: ip hostname alias

The ip address of my computer on the network is
This is just a small home office lan so there are a few computers and we don't have anything fancy going on. Another reason I'm confused iswhere it asks for the FQDN... we have a domain for our website but that server is collocated. If required I can point a subdomain to this computer.

i have tried manually editing the file to show adomainname zcs but after doing so I was unable to browse the internet so it seems like that wasn't the right way to do it.

I have taken screenshots of what I think are all important places to help figure this out.

Thanks so much

FYI, my goal is to install zcs for the purpose of switching from ms outlook 2002 to zimbra desktop and I understood this was the only way to do it. (create imap account on zcs, move all old mail from outlook to the imap account, then use zdesktop and store all the messages locally)