Social security only becomes taxable when added to sufficient other income. If you are otherwise required to file a tax return, you do need to enter it in Turbotax (TT). TT will determine the taxable portion.

Social security (including SSDI) becomes taxable when your income, including 1/2 your social security, reaches:

Married Filing Jointly(MFJ): $32,000

Single or head of household: $25,000

Married Filing Separately and lived with your spouse at any time during the tax year: $0

After TurboTax (TT) calculates the taxable portion of SS, it puts the total amount of SS on line 20a of form 1040 and the taxable amount on line 20b (lines 14a&b of form 1040A). TT also produces a worksheet  to show how the taxable amount is calculated. Although most people pay tax on 85% of their SS. it can be less for lower income taxpayers.

Understand that all rental activity is passive. THerefore rental losses can only be deducted from rental income. Once those losses get the taxable rental income to zero, that's it. You're done. Any excess loss is automatically carried over to the next year.

It is *extremely rare* for rental property to actually have tax able rental income at tax filing time. Particularly if there is a mortgage on the property. Just the allowed deductions of mortgage interest, property insurance and the depreciation you are required to take by law, is usually enough to "zero out" the taxable rental income.

Add to that your other allowed and deductible rental expenses and that's what makes it rare to ever have taxable rental income. So it's much more common for your passive carry over losses to continue to increase with each passing year. You can't actually realize those losses until the year you sell or otherwise dispose of the property.