Herb, if the booking site refers to as Bavaro, you will be in Bavaro. If Punta Cana, you will be in Punta Cana. Basically, they are two different hotels for accounting purposes (they have two different receptions, and two different accountings) and two different bracelet colors. They are mirror images, but have each its own restaurants, entertainment theatre etc. Usually room interchanges between Bavaro and Punta Cana rooms are not allowed, as they are separate for accounting purposes (for services purposes to guest, you can use either one).
But beware, the resort is LONG (it has about 1 km from reception to the beach). So even if both you and your friends stayt, let's say in Bavaro, you can be far away from each other, while you can be accross the walkway (50 mts) even if one stays in Bavaro and one in Punta Cana.
So there is no easy answer. Your best bet is booking in the same resort name and calling reservations (809-5521444 ask for reservations) to put a request to both reservations to be assigned rooms close together.
Anyhow, you won't have to walk miles... the maximum would be 1 km, about 0.6 mile