If social security benefits are your only income, they are not taxable and you are not required to file a tax return. If you had federal tax withheld from your social security, you should file a tax return to get a refund of the tax withheld.
Mortgage payments can only reduce taxable income so that you pay less tax because you have less taxable income. If you have no taxable income, there is nothing to reduce.
The deductible expenses of home ownership which include mortgage expenses and property taxes are itemized deductions. First of all, you can't enter itemized deductions using the Free Edition. You must upgrade to Deluxe.
If the total of all your itemized deductions is more than your standard deduction, you may get a tax benefit if you had taxable income after deducting the standard deduction.
