my key is stuck on and the car is running

There are two things that can jam the key: steering lock, and shifter. Steering: Yank the steering wheel hard to either side while trying to turn the key. Do not force the key. Shifter: if you parked on a hill, and the car rolled while in park, it could be jammed against the 'pawl' that prevent the car from rolling. The only way to "unstick" this without possible damage is to move the car gently in the opposite direction. Get a bunch of friends to push, or use another car with plenty of cushion between the bumpers to nudge the car. You can try to forcefully move the shifter but you risk damage to the tranny.