Hello @Mahesh ,
Thank you for your question.
Microsoft does not have windows server 2016, what is recommended now is to get windows server 2022 through the link below:
https://www.microsoft.com/en-us/windows-server/pricing?SilentAuth=1&wa=wsignin1.0
If you do not want to stay on windows server 2022 and want to downgrade by requesting a downgrade key to return to windows server 2016
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