Leaving insider program and going back to released Windows 11 version 25H2 depend on which build you have installed.
If you have build 28xxx or 29xxx then you have to do clean install of released version 25H2.
If you have any 26xxx build then follow these steps:
1). Download ISO for released version 25H2 https://www.microsoft.com/en-us/software-download/windows11?msockid=13c4190001016d9f341a0d8c008e6cab
2). Delete WindowsSelfHost key from registry to get device out of insider progra,m
Open regedit Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsSelfHost Right click WindowsSelfHost -key and select delete. Restart.