Windows 11 includes intelligent features that can manage brightness for you based on your environment.
In this case, you must use the physical buttons on your monitor: how to turn down brightness on windows 11
These common methods work for most laptop users and some integrated desktop systems. Windows 11 includes intelligent features that can manage
: If your device has an ambient light sensor, you can enable "Change brightness automatically when lighting changes" in the Display settings to let Windows handle adjustments for you. how to turn down brightness on windows 11
Change display brightness and color in Windows - Microsoft Support