As I stated before “the dimensions (Height, Width, Depth, and Space-Time), particles, and energy that make up the universe came into existence at the beginning (The Big Bang).”
No, they did not come into existence at the Big Bang. For that to happen you would need a state of non-existence and a state of existence and some transition between those two states. Nothing like this is suggested by the Big Bang. There is simply existence.
Space-Time does not simply exist in this universe, it is a part of what makes up this universe
True
it is Space-Time that dictates that this universe, and everything in it, must have a beginning and therefore a beginner (I.E. causal agent).
The "beginning" as you call it is simply one "end" of the universe. It needs a causal agent as much or as little as any other point in space-time.
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