My daughter has 3 W2 forms from 3 different employers. How should those be input?

[Texas Roger]

She would enter each of them one at a time on her tax return. 

[Texas Roger]

After entering the first one, click on "Add a W-2 for (her name)" Do the same thing for the 3rd one.

[HelenC12]

Texas Roger is correct. 

Each W-2 should be entered separately on her income tax return, not on your income tax return. You may even be able to import them if they are a TurboTax partner. Please see How do I import or enter my W-2 in TurboTax Online?

Start with the TurboTax Free Edition. If she needs to upgrade, TurboTax will let you know.