Hi,
Thank you for posting your query. According to your description, you are intended to enable SSO RDP. Here are some hints for you and hope it will be helpful.
How to enable Single Sign-On for my Terminal Server connections
https://techcommunity.microsoft.com/t5/microsoft-security-and/how-to-enable-single-sign-on-for-my-terminal-server-connections/ba-p/246523
Best Regards,
Grace
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