I agree that the switch may be the likely problem.
Step on the brake pedal and see if the brake lights come on.
If they don't, check the brake light fuse to see if it is blown.
If they the brake lights come on, then turn the key to where the steering wheel unlocks, but no lights come on. Set the park brake and see if the shifter will shift into neutral.
If the shifter moves out of park, then you will need to have someone determine why the shift interlock actuator isn't getting power when the brake pedal is depressed.
But if you have done any towing recently, I would be that the fuse has blown.