A neutron star is already the remains of a massive star that has run out of fuel.
Neutron stars do not have fuel. A neutron star is a remnant of a star that has already died.
No kind of star.
a dwarf star
hydrogen
A typical star starts out with a lot of hydrogen-1. This is the star's fuel, which is gradually converted into helium-4, and in some cases, into heavier elements.
A star
A star
a fossil fuel
star
It is a binary star
When a star has burnt up all of its fuel and energy, it will collapse.