The KJV and YLT (which both convey the singular 'thee' when it is necessary to do so) have :
And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven. [KJV]
and I will give to thee the keys of the reign of the heavens, and whatever thou mayest bind upon the earth shall be having been bound in the heavens, and whatever thou mayest loose upon the earth shall be having been loosed in the heavens.' [YLT]
The interlinear of the Biblehub presentation shows that the word σοι, soi, (to you) is grammatically singular in each case.
"PPro-D2S" = Personal Pronoun - Dative 2nd Person, Singular.
It is noticeable that Peter was the first to preach the gospel to the Gentiles, requiring the vision of the sheet and the unclean and clean animals to educate him into doing so, before meeting Cornelius at Caesarea, (Acts 10).
And it is noticeable that Peter may well have been the first to write scripture in the Greek language. (I mean, obviously apart from translating Hebrew to Greek as in LXX.) His first epistle is addressed to the diaspora and is, arguably, the first scripture written after the ascent of Jesus Christ. Some, of course, will dispute this. It cannot be proved.
It could also be said that Peter "unlocks" the writings of Paul by giving his approbation to Paul's words, calling them "scripture", 2 Peter 3:16. Again, this is an interpretation.
But the above indicate what might be the ways in which we see Peter using the "key" of Christ-given authority to unlock that which was previously beyond reach.