Hello. The group registrations do not have a limit to how many people can be included in the group. The way it works is the registrant would enter how many are in the group, then proceed to enter data for member 1, member 2, member 3, etc then end with the final billing info. You can configure what fields are presented for each member and then which fields are given for the final billing.
You can also setup group discounts if needed, where at a certain number of members, the price per person is reduced. You can setup up to 10 different group pricing levels for an event.