As long as you haven't yet e-filed your return, you can go back to the "Wages and Income" section and enter your W-2 info.
No need to start over. Hopefully, you haven't filed yet!
*** I am NOT a tax expert. I am a seasoned TurboTax user, and volunteer to provide assistance to TT users. Nothing I post is to be considered TAX ADVICE; I bear no legal liability for responses.***