I have been working on the Microsoft Security Graph API to get the reports.
I have created a PostMan collection put it on the GitHub Repo.

https://github.com/pankajsurti/MicrosoftGraphSecurityAPIPostMan 

I have found following articles very useful.

https://aka.ms/GraphSecurityDocs

https://aka.ms/GraphSecurityAPICode

https://aka.ms/GraphSecuritySolutionsConnectors

https://aka.ms/GraphSecurityWhitePaperSevenWays

https://aka.ms/GraphSecurityQuickStarts

https://aka.ms/GraphSecuritySDK

https://aka.ms/GraphSecurityConnectorsBlogPost

https://aka.ms/GraphSecurityPowerBIConnectorBlogPost

https://aka.ms/GraphSecurityPowerShellModulePost

https://aka.ms/GraphSecurityCuratedQueries

https://aka.ms/GraphSecurityJupyterNotebooks

https://github.com/Microsoft/MicrosoftGraphSecurity

Five cool security apps you can build using Microsoft Graph | BRK3073
https://www.youtube.com/watch?v=Klc9z7jbQio