To get to the part of the admin center where the Office 365 Groups controls are, go to Office 365 Admin center | Settings | Services & add-ins. Scroll down the page and click on Microsoft Teams, as shown in the following screenshot:
You must be a global admin to manage these settings.
Once you click on Microsoft Teams, you will get a side panel with settings:
Make sure you are aware of the notations at the top of the panel, as shown in the following screenshot:
Let's go through the Tenant-wide ...
