List of some of the most useful multi-monitor shortcuts for Windows

Win + P: Open the Project menu to choose how to use your displays (PC screen only, Duplicate, Extend, Second screen only).
Win + Shift + Left Arrow / Right Arrow: Move the active window to the monitor on the left or right.
Win + Left Arrow / Right Arrow: Snap the active window to the left or right half of the current monitor.
Alt + Tab: Switch between open applications across all monitors.
Win + D: Show or hide the desktop, minimizing all open windows across all monitors.
Win + M: Minimize all windows across all monitors.
Win + Home: Minimize all windows except the active one across all monitors.
Win + Number (1-9): Open the application pinned to the taskbar in the specified position (works across all monitors).
Ctrl + Windows + Left Arrow / Right Arrow: Switch between virtual desktops on the left or right, which can be useful if you have different setups on each monitor.
Win + Z: Open the Snap Layouts menu (available in Windows 11) to choose a specific layout for snapping windows