Hello, this is Emily.
You should be able to puchase Windows 11 from Microsoft https://www.microsoft.com/en-us/d/windows-11-ho...
The license is delivered to you as digital license, meaning your Microsoft account is the license itself. As long as you set up the computer to sign in using your Microsoft account, it can activate your Windows. But a product key is usually emailed to you within 24 hours after you received the purchase confimation email. You don't need the actual product key to activate, but it is good to have it handy in case of future troubleshooting need when changing hardware, etc.
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