You have no evidence at all that anything, anything at all, is "infinite, and therefore, always was and always will be" because in order to have this evidence you would have to be "infinite, and therefore, always existing and always will be" in order to gather enough evidence to prove and validate the premise. There is simply no way you can know this.
God created time for our benefit, but is not bound by His creation.
Begs the Question that you 'know' that God created time. There is no way you can know this. Where and how did you gain this knowledge? Assertion Without Proof.
The universe, on the other hand, had to have a beginning.
Again, how do you know this? The Universe "appears" to have had a beginning, but you cannot "know" this. Assertion Without Proof. Best Supposition, at best.
The question remains, if everything had a first cause, what was the first cause for God? Otherwise, everything didn't have a first cause, (because God didn't) and why choose God as not having a first cause rather than the Universe?
Faulty logic.
Yes, a metaphysical origin ordered by a orderer to conform to the laws of physics.
SAME question.
Why did God have to come from anywhere?
Why did the realm from which the Universe sprang have to come from anywhere?
God is infinite, and therefore, always was and always will be. God created time for our benefit, but is not bound by His creation.
The substrate of the Universe is infinite, and therefore, always was and always will be. From it sprang time, but it is not bound by time.
There, now, see how easy that is?
The universe, on the other hand, had to have a beginning.
The predecessor of the Universe, on the other hand, didn't.
There, just as good as your version.