It's an interesting question and science is working on it. I assume you're up to date on the BB theory and the accumulated evidence supporting it?
If the BB theory is essentially correct, and it certainly appears to be, then at some point in the past, all the energy in the universe was contained within an exquisitely small space of unfathomable temperature, whence it erupted to form particles, and atoms, and matter, and the forces, and every other aspect of reality.
My own view is that spacetime exists because energy does, not the other way round where energy is thought to exist within spacetime. Thus the universe exists because energy does. And if I'm right then there are no questions about beginnings, just properties of energy. That, as you can see, avoids all questions of infinite regressions, and so on.
If you think of energy instead of gods, you'll have many fewer problems. For instance, you'll be able to understand why the universe behaves exactly as if gods only exist in the imagination of individuals.
Pardon? Please quote me a reputable scientist propounding this so I can see what you're actually claiming, since your sentence makes no sense to me.
My hypothesis that energy is prior, solves all that.
They don't insist they're right. The don't claim that findings of science, based on empiricism and induction, can ever be absolute. But their conclusions are vastly better founded than those of simple believers because unlike them (a) they reason honestly and transparently from examinable evidence and repeatable experiment and open their conclusions to debate and (b) the question they're trying to answer is, what's true in reality? (not, what's true in imagination).
Time exists, in my hypothesis, as a property of energy, and thus its beginning isn't a problem.
Not much of which concerns the title of this thread.