On the question of the possibility of intelligent design / a "creator" the only sensible stance is to be agnostic. The mysteries of the universe are so vast and deep that it's very possible (probable) that no single human mind COULD even begin to comprehend it, even if it was laid out in the simplest possible terms... And it isn't, so we're very unlikely to ever figure it out on our own. Maybe some sort of advanced artificial intelligence could in a few hundred years? Who knows.
However
Being open to the possibility of *A* god or god-like entity of some description is completely different to being open to the possibility that any one human religion is accurate. Some seem to believe that the thinking of "no one knows the truth for definite... So it MIGHT be Evanglism / Islam / Buddhism!" is a sensible or logical stance. It isn't. The existence of multiple religions, and the fact that NO two separate groups of humans / civilisations have developed exactly the same religion without it spreading human-to-human, makes it almost infinitely unlikely that any of those religions came from on high or contain any sort of universal truth. The only logical conclusion is that they are simple human attempts to understand the mysteries of existence and nature, and to ground and humanise the terrifying vastness of the universe. A comfort blanket, or maybe you could say a "dome of explanations", to shelter from the infinite vacuum of the unknown that lies beyond.
Those unknown aspects of space and time might contain intelligent design. That's very possible. You could call that "designer" God. But it's not Abrahamic God, or any other human god.
Human religions and their rules are collections of fables, myths and legends... Stories we've used to get our heads around it all. No different to Greek gods or (pre-Christian) Roman gods or Norse gods. There is zero logic in believing any differently. Especially given that all of those ancient peoples believed in their gods just as strongly as modern believers do today

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