Hello there,
Do you have the latest version of MDT and ADK installed? Have you tried deploying the stock OS from the ISO to see if your MDT Server is capable of deploying Windows 11?
This article provides details of any current known issues and limitations with the Microsoft Deployment Toolkit (MDT). It assumes familiarity with MDT version concepts, features, and capabilities.
https://learn.microsoft.com/en-us/mem/configmgr/mdt/known-issues
Hope this resolves your Query !!
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