I saw someone break it down into math and the numbers are insane. The chance of YOU existing: an infinite universe full of multi universes, the universe creating earth, the probability of a single protein forming by chance, the absolute miracle that is complex lifeforms, the many different types of humans dying off and leaving modern humans, those humans surviving, war, famine, your mothers family tree, your fathers family tree, your mother and father meeting, that one sperm finding an egg.
I have read it's 1 in 400 trillion. But that might just be the sperm and egg part without the other stuff.