New User - Some doubts

[Snoopy8]

The VMC viewer part is ok, and the computer will boot into a login and password

I see that if I enter the IP address of the other computer on a web browser, the GUI screen appears

Welcome to the forum. If you see the GUI screen, you have successfully installed and SnakeOil OS is running. 
 

Under Music servers, what do MPD (vr17), MPD (dsd-rt), MPD (v19), MPD (v20), Logitech, XMMS mean?
Then if I untick Media Servers, Music Clients pops up
Again, what do these options mean?

Then the main question I suppose is:  How do I add music to the list to play it?   Is there a list of albums, etc

SnakeOil provides the capability to manage Music Servers e.g. MPD. Logitech to read and organise music libraries, and play music via usb (& other connections) using a music client.
https://www.snakeoil-os.net/wiki/Configu...ic-players

Where is your music located?  If it is on a USB stick in the computer, you should see it in the music library tab.
https://www.snakeoil-os.net/wiki/Configu...ic-library

Assuming you have connected a DAC using USB and your music is on usb stick, try with Logitech Media Server as your music sever, and Squeezlite (any version) as your music client.   You should then be able to use your browser to play music
https://www.snakeoil-os.net/wiki/Players...queezelite