Im not sure just how the autopilot works, specifically in relation to a planned flight. Any info would be appreciated
It varies a lot from plane to plane, but the FSX default aircraft all work pretty much the same. Most of the planes have a GPS/Nav switch somewhere, when set to GPS your indicators and autopilot will follow the flight plan that you have loaded in FSX. Set to Nav they'll follow VOR stations. The airspeed and altitude settings are fairly self explanatory...
Autopilot's kinda complicated, i'd advise you to spend some time looking through the help center to learn about it and then come back if you've got any more specific questions. Good luck!
thanks for that.