How can i add my pay stub for the advice?

What do  you mean "for the advice?"    What are you trying to do?   Do not try to prepare a tax return using a pay stub.  You will not have the right information to enter into the boxes--the information on a pay stub will not match the W-2 you will receive from your employer by the end of January.

Are you just trying to use the taxcaster tool for an estimate?  You can use your pay stub for that but understand it will only be an estimate.

https://turbotax.intuit.com/tax-tools/calculators/taxcaster/

Or----was "advice" a typo----and did you mean the "advance"--refund loan?  You cannot get the refund advance using a pay stub.  The refund loans will not be available until January and you have to use your W-2 to prepare the tax return.

TurboTax will be offering a refund advance loan —but not until January.  And you do not get the money until the 2020 e-file has been ACCEPTED by the IRS.You also have to agree to receive your refund on the prepaid TurboTax Visa.

https://turbotax.intuit.com/refund-advance/