You'll then join matchmaking and travel to your server! Press Start, then Confirm to create your world. You can then choose your game mode, World cover image, and advanced world settings, including setting your World Seed. Select 'Create New World', then choose a Save Slot to save your World in. Friends can permit you to join their world even while they're offline, if they share their Key with you while you're in that world together. You can then choose to create a new world or join an existing world. From here, you can party up with your friends, or choose Select World in the bottom left to load available worlds. After selecting LEGO Fortnite, you'll arrive in the LEGO Fortnite lobby.