Upgrade to Windows 10

https://www.cnet.com/how-to/how-to-download-windows-10-for-free-now-that-windows-7-is-dead/

I have tried the link above and it works fine.

Don’t forget to backup all user data first, including stream Autocomplete and archive any IMAP email accounts to PST first.

This then activates your digital license with the Windows 7 activation key OK