If you have not filed your tax return yet or if you filed and it was rejected, type W-2 in the search box and click on jump to W-2.
If you efiled your tax return and it was accepted, you must wait until you receive a refund (if you are getting one) and then you can prepare, print, sign, and mail an amended (changed) return form 1040X to make the changes. Form 1040X is expected to be available in TurboTax on 2/14/19. Do not change your original return until you begin the amended return. Do not spend your refund if you got one because you may owe taxes with your amended return.