I think we need to start over.
Unreal Engine uses a Server & Client model. The server is the big boss and decides what all the clients connected to the server will see and experience.
For instance, I can play a sound on the client, but if I don’t replicate it to the server, it will not play for any other client.
You can create a multiplayer game with only blueprints. You use events to send data and to and from the server.
The character blueprint is by default replicated for it’s base set of animations. However, if you add a sprint function to make the character run faster, you would need to setup the replication for sprinting yourself. I think some functions like jumping is also replicated by default.
Have a look at this: https://youtu.be/XknYqK3qiMI?si=gKbt69FSlVNDOS7H