Formation of Neutron star vs Black Hole.

 When the star runs out of nuclear fuel, some of its mass flows into its core. Eventually, the core is so heavy that it cannot withstand its own gravitational force. The core collapses, crushing together every proton and electron into a neutron which results in the giant explosion of a Supernova. The remnants of the stellar core which are left after the supernovae explosion will follow one of two paths: neutron star or black hole.

1. If the core of the collapsing star is between 1-3 solar masses, these newly-created neutrons can stop the collapse, leaving behind a neutron star.
2. If the Star has a higher mass, it will continue to collapse into stellar-mass black holes.

Above is the picture showing the life cycle of a Star.