No. A 2020 W-2 cannot be entered on a 2021 tax return.
You will have to amend the 2020 tax return to add the W-2.
See this TurboTax support FAQ for amending a 2020 tax return - https://ttlc.intuit.com/community/amending/help/how-do-i-amend-my-return/00/27439
