First of all, this game is not played with other humans. You are playing against bots. This means it's a free-for-all between you and a bunch of AI. You are dropped into an ongoing game, which means some bots could already have taken a chunk of the arena.
Of course when you play the game on your phone or pc, you'll eventually realize that if you unplug your internet or go into airplane mode, that the opposing players are just bots doing their thing. They're not real, they're a lie, a fraud, it's just bots pretending to be people.