@J-3804, Thanks for posting in Q&A. In Intune, there's feature under Endpoint security > Account protection>Local user group membership to manage local user group membership. We can choose Remove (Update) if we want to remove specific user from local administrators group. Here is a link with more details for your reference.
As a note, removing the built-in Administrator account from the built-in Administrators group is blocked at SAM/OS level for security reasons. Attempting to do so will result in failure.
Hope the above information can help.
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