Question

What is the best way to revise the sentence?

I had to prove my identity to gain entrance to the building, I was required to fill out an impressive number of forms.
I had to prove my identity to gain entrance to the building; I was required to fill out an impressive number of forms.
I had to prove my identity, to gain entrance to the building I was required to fill out an impressive number of forms.
I had to prove my identity: to gain entrance to the building I was required to fill out an impressive number of forms.

Answer 1

Answer: I had to prove my identity to gain entrance to the building; I was required to fill out various numbers of forms.

Explanation; The best way to revise this sentence is to add a semi colon.