I marked the part you asked about.
It doesn’t explain how the control look like (simple can/can’t enter the world where “can” means all possible actions apart from already beaconed area where permissions rules apply, or will there be “world permissions” meaning someone can get in but not necessarily build or break blocks etc.).
James’ first is the worlds we play on now.
James’ second is what I called rented.
James’ third is what I called private.