Beta IOS updates

It already downloaded the update before you turned off beta updates. Please do a forced restart, check to make sure beta updates is still off after forced restart, then turn your iPhone off and back on.

Force restart iPhone - Apple Support

If you’re not familiar with the procedure review the instructions. It does more than just turning your device off and back on.

You’ll need to backup your device, erase it and restore your device from the backup.

I’m not sure why you think you won’t have the public release, the beta will expire and not be available.

Have you tried restarting your iPhone? If so and that hasn't helped, then you may just have to ignore those updates, or revert your iPhone back to the release version of iOS, currently 18.1.1.

Regards.

You just have to ignore it, as varjak paw suggested.