You can choose to allow all the participants to join the Room or allow a specific group to join the room.
You can also keep the room Private or people with code can join the room.
Login to Dashboard > Choose a particular event > Rooms > Click on 'Add Rooms'.
Allow all participants to join the room:
Under 'Who can join the Room' select 'Anyone'.
Allow specific groups to join the room:
Under 'Who can join the Room' select 'Specific Groups'.
In 'Group' select the group that can join the session.
Coded Room:
Participants with the assigned code can only enter the room.
Under 'Who can join the Room' select 'Coded'.
Private:
This room will be hidden from all the participants and will be visible to the participant you have added to the room.
Under 'Who can join the Room' select 'Private'.