help with multiplayer

@grazer here is the game im trying to make. Very simple rock paper scissors game with multiplayer. Im not sure what the “Shared Block” does i want to make it so when someone picks R, P, or S. it notifies the other

shared block is im pretty sure only mobile but i dont know to much about that. you should make one player choose like a(for rock) s(paper) d(scissors) and the other player the arrow keys