On a car with rear drum brakes, FWD, AWD, 4WD all use the rear brakes for “parking brake”. There are some cars, older Saabs for one that the parking brake works the front disk brake.
A Toyota Camry Hybrid could be a whole other animal. There are lots of unique aspects of the braking systems for a hybrid. My guess is it works the rear wheels. Drive yours on a dirt road and at 5 mph pull on the parking brake hard and see which wheels leave skid marks in the gravel.