How to replace the rear brakes on a 2013 Ford Edge?

The piston won't go back in the caliper bore and I can't get the rotor off.

Added (1). I need to replace the pads and rotors.

Disconnect the brake line fitting. Be sure to bleed the brakes after.

Never disconnect the brake line fitting if you're doing normal brake service! Sometimes you need a brake caliper tool to wind the piston back in if it has an integral emergency brake. Sounds to me like you should probably just have a pro do it if you can't even get the rotor off.

If you already have the caliper off and it won't go back on the rotor because the piston is too far out, grab the OLD PAD for it place it back on the piston and get a C clamp and start tightening down on it until the piston is all the way back in place then try putting it back on the rotor. ALWAYS REMEMBER TO PUMP YOUR BRAKES BEFORE DRIVING IT