how do I repair a stripped out screw hole in the wall

I have shimed, I've used hollow wall anchors and pop-rivet nuts (These are special nuts that work like pop rivets,, You screw a special bolt into them, insert in hole in wall,, POP with POP tool, and unscrew the special bolt (Which fits in the pop tool, NOTE you do not squeeze hard enough to break the pin like a regular pop rivet) and then use a bolt instead of as screw that hole.

This works best in sheet metal though, not fiberglass or wood.

Different "Strokes" for different holes in different materials.