it doesn't make sense that we are alive

after all we're just atoms and atoms aren't alive
how is it possible?

Sense is a concept that us living things have created, of course it makes sense. Of course nobody actually knows shit about how life came to be and why, or if there is a why, and humanity only glimpses a tiny pocket of the universe, so don't worry about it. Just stick to the unbelievably tiny context we live in, and think about that. give up