the server always replicate the position, but when playing you are client anything you move in client will not replicate unless you tell server to do that.
Check the part for Command from client to server, instead of bool you can change that to position, then server will take that position then he will move your character for you, the position then will be replicated back to you and other client.
Check this if you want to do in BP Blueprint Networking Tutorials - Unreal Engine