How to find Windows 10 Product Key on a New Computer？
The product key for new computers that come preinstalled with Windows 10 has the product key stored within the motherboard firmware. Users can retrieve it by issuing a command from the command prompt.
Press Windows key + X
Click Command Prompt (Admin) or Windows PowerShell
At the command prompt, type the command: wmic path SoftwareLicensingService get OA3xOriginalProductKey
This will reveal the product key.