Question

What is the first stage in the star life cycle? (not a sea star, star like the sun)

Answer 1

A dense region in a nebula begins to shrink and warm up.

Answer 2

The starting phase for all stars, including our Sun, begins when a dense region in a nebula begins to shrink and warm up. This is usually the result of one of several events that may occur to initiate the gravitational collapse of a molecular cloud

Hope this helps!