I'm sorry for your loss.
Now this is going to be a bit confusing. How did you file last year? If you filed a joint tax return, you should have listed all your combined income (including social security benefits) and let Turbotax figure out what was taxable. If you filed jointly, you have the same AGI, so when filing jointly this year, use the same AGI for both.
If you filed separately (married filing separately) last year, then you made a mistake. If you filed separately, then he was also required to file separately, because his social security becomes automatically taxable when filing MFS. If he did not file, try zero as the AGI for this year. But, you may then have to go back and file an amended return for 2022 and any other year when you filed separately and he had a social security benefit but did not file. You may want to consult with a tax professional.
If you can't e-file using your AGI or zero, then you will need to print your tax return, sign it, and mail it in.
