Hi Piet Kamps,
Thank you for contacting Microsoft Q&A regarding the extension of security updates for Windows 10. I understand the importance of maintaining a secure system, particularly when an upgrade to Windows 11 is not feasible.
To proceed, please download the update KB5063709 directly from the Microsoft Update Catalog using the following link: https://catalog.update.microsoft.com/Search.aspx?q=KB5063709%20
Once the update is installed, the “Enroll now” option should be appeared under Settings > Update & Security > Windows Update. Please note that this option may take some time to appear, as Microsoft is deploying it in phases.
If you have any other questions or need additional assistance, please do not hesitate to reach out. I'm here to help.
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