You would not file another return. You would need to amend your return to add your additional W-2. If your return was accepted, you would need to wait to file your amended return. The amended form in TurboTax until 3/25/21 (subject to change). Right now do not make any changes to your original return.
The IRS states that you should wait for your original return to be fully processed before you amend. The IRS does catch some errors, they do get copies of all W-2's, so they may send you a letter asking about the missing W-2.