I'm looking for a tutorial on how to take two videos and overlay them.
The scene will involve a single actor in two different shots. In one shot, the actor is a suspect in the second shot the actor is the interrogator.
These videos need to be "overlayed" (And I'm not sure overlayed is the correct terminology).
in the shot's will be over the left shoulder of the interrogator and the suspect will be facing the camera for the most part.
I've already started there but i don't see anything that answers my original question.
This is very basic compositing.
Rather than looking for a tutorial or step-by-step answer, you need to learn the basics; when you do, it will be very obvious to you how to accomplish what you describe.
Here is a page that describes various ways of compositing two shots together in After Effects: