I sold my personal residence in 2020 and moved into my rental unit. I have no rental income in 2021. What do I do for schedule E?

Yes, you will have to indicate on Schedule E that the property was not rented for 2021.  Then navigate to the Asset section to dispose of the property. Do this for any other assets you may have been depreciating as well. This will calculate any remaining depreciation up to the conversion and remove the worksheets going forward.

keep track of the cost and accumulated depreciation on those rental assets. when you sell, if you have a gain, the depreciation you took while a rental unit will be subject to recapture even if it's 10 years from now.  once you delete those assets Turbotax will no longer have that data. Both the iRS and Turbotax only maintain returns for 6 or 7 years.

For the rental property you moved in to, you need to convert it and all it's assets to personal use.

WARNING! DO NOT under any circumstances and with no exceptions select the option for "I did not rent or attempt to rent this property in 2021". If you select that option, then the SCH E and all supporting documents along with your depreciation history and PAL history will be PERMANENTLY DELETED. You are warned.

As you work through the SCH E section of the program, (and I can't stress this enough) Read. And. Heed. The. Small. Print. on every screen. It matters, big time.