New to forums, I was trying to take out the axle shafts and my diff pin lock bolt stripped on the first turn of the wrench and can’t get it off and I have no idea what to do.
Any advice?

 

I'd try a stout pair of big Vice Grips to latch onto the head and let me pull as I wiggled the bolt or twisted it left.

If you can get a prybar under the head to try wedging it out as you turn it with a ratchet.

Been doing any one wheel burn outs? Spider gears riding on the cross shaft can get hot and seize to the cross shaft twisting it and shearing the lock pin.