Since you said the IRS gave it to you, are you referring to a 6-digit Identity Protection PIN (IP PIN)?
Is it a new 6-digit IP PIN (Identity Protection PIN) for returns filed in calendar year 2021? We can tell you the proper place to enter it.
Have you already efiled without it, or have you not yet efiled?
I clarified the answer above. I was thinking of a 2020 return and mentioned a 2020 IP PIN, which was a typo (I've since corrected it above.) Actually the IP PIN (Identity Protection PIN) goes by calendar year, not tax year. So for any return filed during 2021, including the 2020 return that people are filing now, a 2021 IP PIN is used. Did you receive a 2021 IP PIN either in a letter from the IRS in December 2020/January 2021, or did you get your 2021 IP PIN using the IP PIN Retrieval Tool at the IRS website? We can tell you how and where to enter it in the TurboTax interview, once you reply with whether you already efiled without it or not.