The basic answer to your question is yes, when the autopilot is engaged the pilots interface with the jet using the flight management computer or various items on the autopilot control panel. With the autopilot engaged it is not necessary to manipulate the flight controls at all. In fact, by design with the autopilot engaged, manually moving the flight controls will in some cases disconnect the autopilot and trigger a number of warnings.
Currently produced autopilots are much more than devices just to relieve the pilot during cruise. Often learning the autopilot/automation of a new jet is the steepest single learning curve a pilot faces when checking out on a new type of airplane-and I don’t even fly an Airbus!