How do you fix car wires that have been cut minivan doors were opening on their own wires were cut so now doors won't lock can the wires be fixed how much?

Either replace the whole wiring harness, or repair them with some crimping butt connectors. Figure out the gauge of wire, get the appropriate butt connectors for it (the ones with the heat shrink are the best kind), strip the ends of both wires, insert the stripped ends into the butt connectors, crimp the butt connectors, heat shrink them, then wrap them in electrical tape to protect them.