How does a black hole form?
THere are three ways by which a black hole may form
1form along with big bang
2 collapse of a massive star when fuel is exhausted It become a supernova. outer layers are puffed out the core collapse to a black hole.
3 collision between 2 neutron stars.
see you tube video . https://www.youtube.com/watch?reload=9&v=7DBKVL9Wqkw