You can easier create reports based on the support views within the cm database. This of course assume that you don't like the existing reports in cm.
As for how this book will walk you throw the steps on creating a dashboard.
https://www.informit.com/store/system-center-configuration-manager-reporting-unleashed-9780134466811
Here are a few other useful blogs
https://www.recastsoftware.com/resources/why-is-it-important-to-use-supported-sql-server-views-with-sccm-reporting/
https://www.recastsoftware.com/resources/what-are-the-supported-sql-server-views-to-use-with-sccm-reporting/