For year 2021, you will be considered as a nonresident.
As a F- visa holder, you have total 5 years being exempt lifetime ( not counting days hence nonresident status) including both J and F visa. Therefore, you would be counting your exempt years start from 2018 until 2022. You will be considered as a nonresident from 2018 until 2022 ( J visa 2018-2020, F visa 2021-2022).
As TurboTax does not support nonresident status, you are suggested use Sprintax to complete your filing of Form 1040-NR.