This article explains how to take a screenshot on a Logitech keyboard. The instructions below apply to all Logitech keyboards, including the Logitech K780 Multi-Device Wireless Keyboard.
How to take a screenshot on the Logitech MX Keys – PC
To take a screenshot on Windows, press the Windows key+PrtScn.
If PrtScn shares a key with another button (such as Insert, Tap, or Delete), you may need to press Fn+Windows Key+PrtScn. To capture only the active window, use Windows Key+Alt+PrtScn.
To take a screenshot on a Mac, press Shift+Command+3. You can also press Shift+Command+4 to select the portion of the screen you want to capture.