Hi Nathaniel,
My name is Igor, it's a pleasure for me to help others and I'll do all my best to help you.
Microsoft warns at https://www.microsoft.com/en-us/howtotell/Shop....
Beware of Product Keys Sold Separately
With the exception of Product Key Cards (PKC’s) distributed with COA’s, Microsoft does not distribute products keys as standalone products. If you see a listing on an auction site, online classified ad, or other online page advertising product keys for sale, it’s a good indication that the keys are likely stolen or counterfeit. If you were to purchase and use a stolen or counterfeit product key to activate Windows installed on your PC, the key may not work for activation, may already be in use on another PC, or it might be blocked from use later by Microsoft when the key is reported stolen.
In general, there are three legal ways for you.
- You may buy OEM packs and install them to your PCs as OEM system builder. See details at https://devicepartner.microsoft.com/en-us/commu...
- You may buy a retail Windows licenses but they are more expensive than OEM.
- It you are a large manufacturer (~10000 PCs/year or more), you may sign Direct OEM contract (DOEM) with Microsoft. It is significantly cheaper than OEM packs.