If the income reported on Form 1042S is separate from the income reported on Form W2, yes you will need to file an amended tax return Form 1040X to report the income and any tax withheld reported on the Form 1042S.
TurboTax expects to be able to begin preparing and filing amended tax returns on March 25th (subject to change - especially with the recently passed American Rescue Plan).
Instructions Form 1042S (see under Purpose of Form reference to Form W2)
