Best start a new thread 
The way VST connect works is that one side (the studio) uses Cubase/Nuendo and the other side uses the FREE VST connect Performer application. You cannot BOTH use cubase.
As both of you have cubase then you can just install:
You really do need to read the documentation - both the PDF and this page:
Note that even though you don’t want to record voices or guitars - you’re probably going to want microphones and webcams at both sides so you can use the video conferencing features…you could get away without them but it’s worth setting them up.