The dashboard provides you with an overview of your Office 365 Groups.
You can review orphaned Groups, inactive Groups, Groups with external sharing, and uncategorized Groups.
The To-do list suggests actions you can take on your Groups.
You can click on any item in the dashboard to review the details in the appropriate section of the app.
Note: You could see a discrepancy between the number of inactive groups and the number on the Take action on x inactive groups card. This is because the card to take action on inactive groups will only consider groups that do not have an entrusted owner.