System Tray Icon Windows 11 -
You use the NotifyIcon component.
HKCU\Control Panel\NotifyIconSettings
Comparison of NOTIFYICONDATA versions Appendix B: PowerShell script to list all registered tray icons Appendix C: Registry export for resetting tray icon settings system tray icon windows 11
If you want to hide the Clock, Volume, or Network icons specifically: You use the NotifyIcon component