There are a few things you should keep in mind when dealing with Office 365 Groups and Microsoft Teams:
- When you create a group, a SharePoint site collection is created behind the scenes; when you create a team, both a group and a SharePoint site collection are created.
- You cannot see the generated site collections through the old SharePoint admin center, only through the new SharePoint admin center (which is still not generally available as of March 2018).
- The SharePoint site collections and groups may also be visible on your SharePoint home page.
- The generated site collection is a partially stripped-down team site. Some site collection features, such as apps, and pages, such as the library templates gallery, are not available; although some may be accessible with URL manipulation, you will not have access to complete actions, such as adding a library...