Undo screws. If they have been painted over many times, place screwdriver in screw slot and tap with a hammer to loosen screws and to make sure screwdriver blade can get proper purchase.
Pull hinge away and place 1mm shim of cardboard or timber to fit behind hinge. Screw hinge back and check door operation. It should have lifted the closing bottom edge slightly. If door still binds, try a second shim. This should fix it. If the door is binding very badly, you may actually need to take the door off and plane the bottom edge, but it’s always worth giving this simple fix a go first.