In the Lists section it is possible to create a list in order to group users.
How to create a list:
1. Left click on Lists
2. Click on more at the top right
3. Name the list in the appropriate List Name space
4. Left click on the plus icon to add users to the list
5. Check the users to add to the list and click Add in a list
How to edit a list
1. Left click on Lists
2. Click on the three dots corresponding to the list to be edited
3. Click on Edit List