3d camera help!

Start with the User Guide. You'll find these tutorials on working in 3D space. You can use a one-node camera or a 2 node camera. Perspective is controlled by camera position and framing by focal length, or in the case of an AE camera, the Zoom value.

The most efficient workflow depends on the style of animation you want to do. Your sample comp would be easiest to duplicate using a one-node camera and multiple views so you could see where the layers are you are trying to focus on.

Another option is to leave the camera in one position, arrange all of your 3D layers in 3D space using multiple views, then add a 3D null to the scene and parent all 3D layers to the null. Then all you have to do is animate the position of the null to reposition the layers in the scene. Again, this is easiest if you have multiple views enabled. 

Looks like the moving of layers and static camera with a big focus distance