It's not clear why your IRA worksheet would have the box checked as though you were in a covered plan at work. If you are using the TurboTax CD/Download version you can override it. Simply right click on the box to override and remove the checkmark. However I would check box 13 for any W-2 form entered before doing the override.
Also, your computer sometimes remembers pieces of information you thought you deleted. It's a good idea to clear cookies and cache on a regular basis because it makes a difference.
The maximum amount you can contribute to a traditional IRA for 2021 is $6,000 if you're younger than age 50. Workers age 50 and older can add an extra $1,000 per year as a "catch-up" contribution, bringing the maximum IRA contribution to $7,000.
[Edited: 03/03/2022 | 8:46a PST]
Right clicking did not let me override the check mark. Initially, I had this problem, but after updating the software it went away. Then, after another update, the problem returned.
If you are retired, maybe you want to enter a 1099-R and not a W-2?
Click this link for How to Enter 1099-R.
To enter your spouse's IRA Contribution: