If you imported your W-2 into TurboTax, TurboTax does not get an image of the W-2 form. It just gets the information from the W-2, and enters that information in your tax return.
If you uploaded your W-2 from your computer, or you entered your W-2 by taking a picture of it with your phone, TurboTax does not retain the picture of your W-2 after the information is entered into your tax return, and the picture is not saved on your phone.
According to the instructions for the employee on the back of your W-2, you are supposed to save your W-2 for at least 3 years after you file your tax return.
