Here's what I'm curious about. So this hydrogen gas collects and at some point, it eventually becomes a star. What does that process look like? If you were there as a witness to the formation of a star (greatly speeded up, of course), what would you see. What stages would the gas go through? Would it first form a gas giant planet at some point? With perhaps a solid core of something covered with metallic hydrogen and then hydrogen gas over that? Or does it form differently?
I assume at some point a critical pressure/temperature point is reached and fission begins. What does that look like? Does the whole thing just burst into flames or does it take time?
And somewhat relatedly, I'm curious how large stars form. Why wouldn't it first form as a small star? I have always assumed that once the star ignites, it's going to radiate away any of the collecting gas. But maybe that assumption is invalid. Will the gas continue to collect due to the gravity and the nature of the star simply evolves as the gas collects?
I've never really seen a sort of "diary of a star's birth" kind of description.