After you file

On a personal tax return you cannot apply a current year tax refund to prior year taxes owed.  You can only apply the current year tax refund to the next year's taxes.  If you had a tax debt for a prior year the IRS should have seized the federal tax refund and applied that to the taxes owed.

Federal taxes owed and paid for a prior tax year are not reported on nor deductible on a federal tax return.