The attendee type for each person is set when you create an event booking. You can change the attendee type later if you need to.
Update the attendee type
Open the event booking you want to update, either from the Bookings tab within the event or directly from the Bookings module.
Click the Details tab on the booking.
Under the event attendees list, find the attendee you need to update.
Click the three dots next to their name, then select Change Type.
Choose the new attendee type from the list.
Click OK to save your changes.