This is a future tense of immediate consequence, as in Believe on the Lord Jesus, and you shall be saved. Prophet Peter is offering making an offer: Do this, & God will do that.
You invent a supposed time gap where there is none. The only condition put on men is to repent (have a change of mind from unbelief to belief). Both the baptism of the Spirit & the indwelling of the Spirit are things that God does to man; man doesn't do either. "Be baptized . . . , and ye shall receive" are 2 consequences following repentence, both done by God. And the passage does not say that one follows the other, any more than if I eat green eggs & ham, that means what order I eat them in.
As to making up the mind, for you to have a change of mind from trusting in water/works to trusting the Savior is advisable.
You did not solve your problem only made it worse.
1) you claim "be baptized" means one is baptized with the HS being indwelt by the HS
2) you also claim "gift of the HS" also refers to the indwelling of the HS.
So you have "be baptized" and "gift of the HS" BOTH meaning indwelling of the HS.
Yet you posted above "
This is a future tense of immediate consequence.."
So you have receiving the gift of the HS (indwelling) as the consequence of having been baptized (indwelling). You now have an indwelling (gift) as the consequence of an indwelling (baptized). One would not need the consequence (gift of indwelling) if he already has the indwelling at the point of baptism.
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--Repent
and be baptized are two different things
--heareth
and believeth Jn 5:24 are two different things.
--believe and confess RIm 10:9,10 are two different things
--baptized and gift of the HS would also be two different things as YOU showed with one being the consequence of the other. Cannot be the same thing if one is the consequence of the other having already happened.