The Group Appointment feature is used for when creating new appointments under multiple providers. There will be a separate appointment (for the same time) created under each provider that is added.
The Doctors must be set up within a Schedule Group. Your Schedule view also has to be set to view this Group when booking.
Administration > Schedule Setting > Add a Group
Creating the Group Appointment
Create the appointment as you normally would, clicking a time, then search and select the first patient.
Instead of Add Appointment, select Group Appt.
Instead of Add Appointment, select Group Appt.
You need to select the providers that will be present for the group appointment and then select Add Recurring Appointment.
Here is what would display on the schedule once Added: