When you think about it: We are made out of the same stuff as stars.
Beyond that, we don’t know, because it directly links to the question: What is life?
Surprisingly, scientists do not agree on what life is.
The most credible theory that I know of is that of Autopoiesis by Francisco Javier Varela García and Humberto Maturana. Autopoiesis is Greek for self-creation or self-production. According to this theory, an autopoietic unity, or holon, produces the very parts of which it is made and keeps them in working order by constant renewal. Such a holen works by its own rules. It creates a boundary that distinguishes it from its environment and it exchanges materials with its environment.
A living being then is something that is whole in itself and also part of a greater whole.
You are such a holon. I am such a holon.
And recent discussions also take the earth to be such a holon.