Taxes owed and paid are not entered on a tax return. Just file your tax return as is, the IRS knows the taxes were paid.
Your actual receipt of payment depends on how you paid the taxes owed.
If you paid by direct debit from your bank account using the IRS payment website, it will be the confirmation number you received and your bank statement showing the payee and the payment.
If you paid the taxes owed by credit card, it will be your credit card statement showing the payee and the amount paid.
