Connecting Faces & Single Face bevel

Is there a way that Blender can join two selected faces? Eg, two cubes are spaced apart, and I wanted to join a face from cube A and a face from Cube B?

And

I noticed that when I bevel, all the faces in the model are Beveled. is there a way Blender can Bevel only one face on a mesh? I even tried selecting one face, but it still did not do anything.

For connecting the faces use the bridge script. Bevel use bevel center. both found when in edit mode -> Mesh(button on the header of a window) -> Scripts

To create a face, in edit mode, select the 3 or 4 vertices that are to be the corners of the face and press F key.
To bevel selected edges, open a window and change it to a scripts window . look for the bevel script in the mesh dropdown menu. This script will allow you the control to bevel only the selected edges.