Hi @wdar
I completely feel with you. Coming from MS Windows it is a shock not to have a graphical desktop environment available. There just isn’t any! So connecting through a remote desktop connection (Typically a VNC connection when it comes down to Linux based computers) you would end up with a nice black terminal screen.
This might be a shock for you but honestly, you don’t need a graphical environment when you have the combination of the webinterface of the NethServer servermanager plus a terminal/SSH interface. Yes you will have to get used to commandline use. But once you get the hang of it, you will find it is such a powerful tool, you don’t want to go back to a graphical environment!
Do start reading… a LOT! Do install NethServer as a virtual machine, for instance in Virtualbox, and start using that terminal Try commands and see what they do. (deliberately) Make mistakes and try to fix them.
Now getting to your internal mailserver. Setting up a mailserver in NethServer is like 3 clicks of work. There are quite some howto’s available in these forums. Try the search function. You can also start with this topic: NethServer for dummies: Email server
If you have any further questions, don’t hesitate to ask and enjoy your journey ‘from Windows to Linux’.