You do not pay your tax to TurboTax, and TurboTax does not pay your tax to the IRS. If you chose to pay your federal tax by direct debit, TurboTax just sends your bank account information to the IRS along with your tax return. If you did not pay by direct debit, you have to either mail a check to the IRS, pay online on the IRS web site, or pay by credit card through a third-party payment processor.
Your proof that your tax was paid is your bank account records or credit card statement showing the payment to the IRS.
