Well all I know if u must have friends so they can invite to a party and play minecraft
Correct. To play multiplayer you must have friends on PSN who are also actively playing the game. Your friends can also join the same session if the host has friends of friends enabled. For instance, if you join friend X's session and friend Y wants to join you, X must have friends of friends enabled. In a way, the multiplayer for consoles is set up like PC's white listing so that randoms can't typically join your world just to mess things up. Friends can (or should be, haven't played console since I set up my pc) send you invites to their world as well. All this is granted that the host has their world ticked as online.