it is embedded in the bios. Open a PowerShell (Admin) and enter wmic path SoftwareLicensingService get OA3xOriginalProductKey press return. A 25 character key will be displayed if it is available.
Can I get Windows 10 key from BIOS?
If you need to find the product key for your Windows 10 installation, you’ve got a few options. The key can be retrieved via the BIOS i.e. the bootloader of your system or the command window. You can also use external software to retrieve your Windows 10 key.
Is Windows 10 license tied to motherboard?
When installing Windows 10, the digital license associates itself with your device’s hardware. If you make significant hardware changes on your device, such as replacing your motherboard, Windows will no longer find a license that matches your device, and you’ll need to reactivate Windows to get it up and running.