The rear breaks the callepers wont compress to put pads back in what do i do please help

You have to check the caliper piston if it has two v shape reliefs then you need to try using plier tha will fit in the v's and turn counter-
clock wise. If no v's on piston then look on the back of the caliper between the brake hose and hand brake cable bracket. There is
a hexhead plug, 12 or 14 mm, remove this, now you need a 5 or 6 mm allen wrench. Once again turn adjustment gear counterclockwise to pull the caliper piston back. Every time the hand brake is used, it will turn the adjuster if there enough free travel.