There are two versions of Google Groups—the free version for everyone, and a version for organizations (work, school, and so on). The tasks you can do and features you can access depend on which version you have. If you're signed in with a work or school account, the tasks and features available to you are customized by your administrator.
If you have both versions, you might need to switch accounts to access the feature you want.
Go to groups.google.com.
If you are using Google groups for business, you will see an 'All groups' option in the left hand panel as shown in the images here.
Groups for Business
Standard Groups