Green elephants are not a requirement for our existence.
The beginning of space and time are.
For that something outside of space-time must exist that created space-time.
Unless you are denying that we exist I am asking you to present another possible way that our universe has been created. Because according to thermodynamics energy cannot be created or destroyed.
Yet our universe does seem to contain energy so where did the energy come from? If you say energy can come out of nothing you’re disagreeing with everything we know about physics.