You are not supposed to associate a weapon as a peer.
Only use the Multiplayer->Associate on the object (character) the players are controlling.
Also:
"On Peer Connected" triggers only for players connecting, but never for the Host itself.
Also "Pick a random Spawn1 instance" doesn't do you any favor either.
I guess i don't have to teach you what random means.
There are several other issues though.
I highly recommend to read the official tutorials or look at the examples before you continue.