Limit access to a single user login in Linux

Maybe a dumb question, but I can't find the answer..

Posts generally talk about access to the relevant computer as if it is a single entity.

I want Team Viewer to connect a remote party to my log-in page only, and from that point for the remote user to look like a normal keyboard type user with whatever powers that user has been assinged by the computer.

How do I do that ?

Thanks in anticipation.