Goto Windows App Top [hot] -

: A powerful manager that adds "Always on Top," "Picture-in-Picture," and "Opacity" controls directly to window title bars.

Windows has a setting that prevents apps from stealing focus. To disable (use with caution):

For developers: You can modify your own program’s window style using SetWindowPos with HWND_TOPMOST . But for regular users? Stick to PowerToys or DeskPins.

A floating window that stays above everything else – video player, calculator, chat, or monitor.