Hi @Jing Xu ,
Below Microsoft Graph Security APIs can be used to get Microsoft Secure Scope of M365 tenant. Please refer the below addtional microsoft documentation for Graph APIs & more information:
https://learn.microsoft.com/en-us/graph/api/resources/security-api-overview?view=graph-rest-1.0#secure-score
https://learn.microsoft.com/en-us/graph/api/resources/securescore?view=graph-rest-1.0
https://learn.microsoft.com/en-us/graph/api/resources/securescorecontrolprofile?view=graph-rest-1.0
https://techcommunity.microsoft.com/t5/Security-Privacy-and-Compliance/A-new-home-and-an-all-new-look-for-Microsoft-Secure-Score/ba-p/529641
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