Survival MP is one of three game modes in 7 Days to Die. This is the multiplayer mode that can consist of both PVE and PVP (depending on your server's rules). This mode can be played with a private group by creating a game and inviting players to it (currently available through Steam, not sure how it works on console), on a private, rented/hosted or public server. Players who host or rent a server or create a private game will have options to set the rules and difficulty levels. Official servers will have pre-set rules - generally default options. There are server hosts and other companies that offer server managers to make rule changing on rented servers easier.
The server admin will decide which type of map is available to players. This can be Navezgane (currently the default map) or a Randomly Generated map. Prefabs are available for non-official servers but although they add addtions like extra buildings to the map, the map must still be set for Random Gen.
Players will spawn into the game on a random spot on the map and will be equipped with a few items in their inventory. Starting items include: