You can make a multiplayer game using Kaboom in Replit with Nakama as the backend server. You need to create an account, set up Nakama and Kaboom environments, and connect them together to enable communication between players. The process involves creating a match, joining it, sending player data, receiving updates from other players, and updating the local player object accordingly. This allows multiple players to see each other's moves in real-time, enabling multiplayer gameplay.