This is similar to asking, if God made the heavens and the Earth, where did God come from? Now, before you dismiss this as nonsense, it really does get to a fundamental flaw in logic. Theoretical physicists like Hawking thought the question of what came before the Big Bang as preposterous because time itself started at this moment. It would be like asking what is North of the North Pole? If you go by this logic, you must at least ask yourself how something like spacetime can pop into existence from nothingness.
There are theories, like Roger Penrose's conformal cyclical cosmology and M Theory. The question though comes down to some iteration of a loop. Who created God, what happened before the Big Bang, and even what happens to my consciousness or "me" at death is questions that many people think they know the answer to, but deep down I don't think anyone really can say they can answer with an absolute truth.
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