A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Hi anonymous user,
- In SharePoint Online admin center, there are some default reports for you to monitor your SharePoint online. It is like this:

And you can use the alert policy in the security and compliance center to set alerts: alert-policies
Besides, here are some third party tools that may help you:
https://www.manageengine.com/products/applications_manager/help/sharepoint-online.html
https://www.office365mon.com/
2.The Microsoft Secure Score is what you want to improve secuity score: microsoft-secure-score
Third-party information disclaimer:
The third-party product that this article discusses is manufactured by a company that is independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of third-party products referenced in this article.
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