If you want multiplayer, you need a server that runs the Eaglercraft 1.16 bridge.
Playing Eaglercraft 1.16 is unlikely to get you into legal trouble (they target distributors, not kids on a school laptop). But be aware that the experience is technically piracy unless you own a legitimate copy of Minecraft Java Edition. We strongly recommend purchasing the official game to support the developers. eaglercraft 1.16
// Inside the ChunkLoader class (conceptual) If you want multiplayer, you need a server
Let’s be honest: Running a 1.16 world in a browser is heavy. If you are playing on a school-issued laptop with 4GB of RAM, you will struggle. Use these tweaks. If you want multiplayer