Hi,
Something here might help:
Procedure to continue receiving security updates after extended support ends on January 14, 2020
https://support.microsoft.com/en-us/help/4522133/procedure-to-continue-receiving-security-updates
How to use Windows Server 2008 and 2008 R2 extended security updates (ESU)
https://learn.microsoft.com/en-us/windows-server/get-started/extended-security-updates
You'll also find a lot of information on the FAQ page below:
Frequently asked questions about ESU for Windows Server and SQL Server 2008 and 2008 R2
https://support.microsoft.com/en-us/help/4539036/faq-about-esu-for-windows-server-and-sql-server-2008-2008-r2
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(If the reply was helpful please don't forget to upvote or accept as answer, thank you)
Best regards,
Leon