Thank you for posting this in Microsoft Q&A.
As I understand you want MFA to be prompted whenever user tries to RDP to Entra joined device.
This feature is not available for now. RDP client doesn't support MFA. RDP client on Windows doesn't give a layout for MFA prompt.
However, you can submit this feedback in our Azure feedback portal. This platform is monitored by our PM's and they will be able to provide more details on this feature if this is planned for upcoming changes.
https://feedback.azure.com/d365community/forum/22920db1-ad25-ec11-b6e6-000d3a4f0789
Let us know if you have any further questions.
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