By default, only organization owners can add groups.
An owner can choose whether to allow all members of the special "staff" group to create private groups.
Note that groups cannot be deleted at this time.
There are two ways to create a new group:
Visit the help on Group settings to learn about the settings.
Visit the help on Adding/Removing members to learn how to invite or add members.
Where a group's permissions allows people to join without being invited, but their membership needs to be reviewed by a group admin or moderator, the membership request is shown in the For Review dashboard.
It's not possible to remove a group.
You can remove all members and remove sending and visibility permissions, which will hide it from everyone's view except organization owners. This helps you retain an archived copy of all messages.