My neighbor's tree is destroying a wall on my shed, what can i do
That depends, is part of the tree coming onto your property? I believe you can cut limbs off if they are coming over your property line. However, I would just discuss it with your neighbor.
talk to your neighbor about it and if he doesnt want to cut it/trim it call the supervisor for your borough about them to cut it for you
Tell your neighbor to cut the tree or pay for repairs. As the owner he's responsible. If he's unable to cut it, age or whatever, volunteer to do it.