My passenger side front break is locked up how do I release it 2000 durango slt

Loosen the brake fluid bleeder behind the wheel. Follow the Fluid line

Isn't that the thick black one

No, Irodr911 is talking about the bleeder screw on top of the break caliper itself. If the caliper releases when opening the bleeder screw, and you are able to push the piston back into the caliper housing, then more than likely the black break line hose attached to the caliper has collapsed internally and would need replacing. More than likely though, it may be that the caliper is frozen up and would need replacing. I would be just a matter of prying it off after the 2 bolts are removed.

It looks like a grease fitting with a plastic cap on it, takes a a 10 or 11mm wrench