I closed an LLC last year in Texas. I can't find the place on the schedule C in Turbo Tax where I declare that I 'Disposed of the business.' Anyone know where that is?

You need to update your Business Profile which you will see on the page that says Your (name of business) Business. The next screen will say Let's confirm your business info and one of the options will be Disposed of Business in Current Year, on which you will have to Edit the entry to see the screens where you enter information regarding the disposal of your business.

Thanks for responding, Thomas!

The closest I can find to that is 'Stopped Work in 2021'

That has me a little confused. Is there another area that I am missing?

I am sure I am just overlooking something.

That is the box you want to check.  The next screen asks if you sold the business to determine if there's any gain.  If you did not you check "None of these apply" and continue with your business information for 2021.