Group registrations and required fields

We're holding a golf event. I want to have group registration for the foursome of players.

Often, one person registered a group of four golfers. How do I set up a group registration so the team leader (Player 1) can register with required fields for name, address, phone, email but only be required to have name, phone, and email for players 2,3, and 4?

Also, can he leave one blank or write in "To be named later"?

You can edit each field via [ Event Booking -> Custom Fields ] and set the toggle for "Only require for first group member" for each field to YES