The stages in the evolution of a star are very complicated. All stars begin as gaseous pillows in a region of space called nebulae. Stars form in this nebulae when these gaseous materials come together to make a star that goes from 450 times smaller than the sun, a proto star, to 1000 times larger than the sun, a massive star. When the proto star starts to shine it is a sign that it is going through nuclear fusion, when hydrogen becomes helium.
When the star becomes too hot, the helium turns to carbon and the star starts to expand and becomes a red giant. The red giant starts to breakdown, which then turns into a planetary nebula. The core of the star is called a white dwarf until it dies and stops shining, then it is called a black dwarf.
The other kind of star called is a massive star, when a star is made with less hydrogen. As the massive star starts to lose hydrogen, it expands and becomes a super red giant. When this star explodes, the gases released called are supernovas. If the beginning star called was a massive, star the supernova turns into a neutron star, one smallest kind of stars. If the beginning star was a giant star then the supernova turns into a black hole. The stages of a star all depend on chance.