Setup for Plus coaching sessions

I apparently need an audio interface so I can play my guitar into my Mac so Reggie can hear me play. But I also need to speak to him (so I guess I need a mic), and hear him (for which I already have speakers connected to the headphone port.... but how does it all hook up? And do I have to worry about feedback?

I just use a very basis set up, using the laptop cam, mic and speakers with acoustic guitar. Works well. For all the sessions I have gone to this have been the way all the other people have joined. For electric the guitar's are connected to amps so the computer mic can pick it up.

I've ordered a USB mic and hopefully that will be good...thanks!