If you are referring to W2 Box 14, this box has always been used to report miscellaneous things by employers that in the past did not affect tax returns. This year with the changes due to One Big Beautiful Bill Act (OBBBA), box 14 is being used to report qualifying tips, and sometimes qualifying overtime.
If you are not sure what your employer meant by TT, you should ask to ensure that you enter the information correctly on your return.
In TurboTax, enter the description from your W-2's box 14 on the first field in the row. Enter the dollar amount and select the correct tax category that goes with that description. If none of the categories apply, scroll to the bottom of the list and choose Other (not classified). Don’t worry. We'll figure out if it impacts your return or not. If we need more information, we'll ask you.