This article explains how to cancel a Windows update that is already in progress. Instructions apply to Windows 10 Home and Pro editions.
How to Permanently Disable Automatic Windows Updates on Windows 10 (2021)
If you're not quite at the point where the Windows 10 update is installing, but your PC has downloaded the file and the Shutdown and reset options have changed to Update & Shutdown and Update & Restart, you can still stop these updates before they take effect. You just need to prevent Windows' own "maintenance" from happening.
Open the Control Panel and select System and Security from the list of menu options.
Select Security and Maintenance.
