There are different feeds for the different controllers though some smaller airports may have a single controller for Approach/Departure and another for Ground/Clearance.

These descriptions are greatly simplified but should give the idea what each does.

Approach controllers start funneling aircraft towards the airport from about 30-50nm out. They also clear aircraft to fly the approach pattern to their designated runway.

Departure controllers direct aircraft away from the airport and keep them separated from arriving aircraft before hand them off the the en-route "centers."

Clearance gives aircraft their routing. Often it may be the same as the flight plan filed by the pilot or airline but it may be different based on traffic, weather, etc.

Ground controls movement around the airport pretty much all movement on the airport except for the active runway(s). This can include movement on the apron/ramp, taxiways, inactive or closed runways, designated holding areas, etc.

Tower controls the active runways. The tower controller also clears aircraft to takeoff or land. They may also instruct aircraft to go around if needed. At some airports they may also control the taxiways near the active runways.

The live ATC feed for the airport here covers four frequencies. Tower, Approach and Departure (handled by the same controller), Emergency/Guard and the Minneapolis Center (ZMP) sector for this area. I wish I lived close enough to pick up the local controllers because it's really annoying to be listening to something interesting from the local controllers only to have them stepped on by the ZMP controller.