The IRS has not yet issued Form 2210 for 2021. The form is currently not expected to be available in TurboTax until March 17, 2022. The Form 2210 that you are seeing in TurboTax now is incomplete and has not been updated for 2021. Try again after TurboTax designates the form as being available.
IRS forms availability table for TurboTax individual (personal) tax products
