Does the #pratt tag still exist? If so, this deserves one.
The obvious answer to this is to ask what explains God, an infinitely complex and powerful being.
Now, an honest believer - like a certain Doctor of Divinity who taught me once, who was, in spite of everything, a wise man - would say “The Bible starts with the words ‘In the beginning God’, and that’s enough for me - I do not concern myself with what happened before that.”
To concern oneself with what happened before that, one would have to either continue the chain - i.e. assume that God created this reality because God is from a different reality, which would again require a separate explanation for God - or else literally use circular logic, i.e. assume that this reality is circular, and that it created God so that God could create it, with God possibly arising as the combined will of humanity (or some form of artificial intelligence, as that’s in vogue nowadays).
I prefer the Doctor’s view. I do not believe in God. Why ask me, or better yet, a world-class physicist, what happened before the Big Bang? Nobody knows and no-one will ever find out. On the scale of the universe, humanity’s too tiny to ever know.