You wouldn't have to pay to do your return on TurboTax if you didn't actually file your return. You can input your tax information and if you don't get a refund or have to file a return, you won't have to pay anything.
In many instances you would only get a refund of taxes you paid in, so if you didn't have any tax withheld from your SSDI or other income, it is not likely you will be entitled to a refund.
The standard deduction for a single person starts at $13,850 and at $27,700 for married filing joint. If your income is under those amounts, you may not have to file a tax return. Also, all of your social security income is not taxable, so you may be able to make more than the standard deduction amounts and still not have to file a tax return. You can use this IRS tool to see if you need to file a tax return: Do I need to file a tax return
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