You can block Windows 11 using the registry or a portable freeware like InControl from GRC.
Download InControl from https://www.grc.com/incontrol.htm and run it.
Ensure that the version displayed is 10 and Release is 22H2
Click Take Control.
This blocks Feature Upgrades on this PC.
(InControl.exe can be deleted. It only creates the update policy registry values; it doesn't need to be running all the time.)
Important
However, you need to enroll in the Windows 10 Consumer ESU program to get security updates and keep using Windows 10 until October 2027.
See Windows 10 Extended Security Updates | Microsoft Windows