Hello 裕之 伊藤,
Welcome to Microsoft Q&A forum. I'm happy to help.
I understand that you'd like to transfer a license from one computer to another. I see that you have purchase an upgrade to upgrade your Windows 10 to Pro and upgrade it to Windows 11. The answer to this depends on the license you have is an OEM license or digital license. You can check it by going to Settings > System > Activation and select "Activation state".
If your current product key is an OEM key, it's unfortunately cannot be transferred. However, if it's a digital license and linked with your Microsoft account, you can activate it on another computer, but you will need to disable it on the current one. The upgrade to Pro might change the status of your activation, so I'd like to make sure.
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