How to Get the Windows Product Key via cmd in Windows
The simplest way to find the Windows Product Key license is to turn to a privileged command prompt in Windows and execute a command that retrieves the software license product key.

From Windows, open a new Administrator Command Prompt window and then enter the following syntax:

wmic path softwarelicensingservice get OA3xOriginalProductKey

Hit Enter / Return for the Windows product key to be displayed, it is a 25 character alphanumeric string in the format of the following:

XXXXX-XXXXX-XXXXX-XXXXX-XXXXX