How to command dedicated server

Hello everybody,
I’l trying to work with Unet on a dedicated server, i can connect from client to the server but i want the client to call functions on server, i tried [command] but i’m not sure about how it work…

do [command] call a function in the server without having it in it’s in own code?
Or maybe it call the function written on himself (client) on the server?

I’m looking for a way to (if i’m the client) tell the server that i want to use his function named “test()”, RPCs legacy was on the documentation the best way to do it but i’m not sure if it work with UNET …

If someone know how to call function on server with being the client , tell me please…
If you know where i can find some complete guide / information / tutorial about how to work with dedicated server …

Thanks for help guys.

how do you connect to server? are you using networkmanager or NetworkClient and NetworkServer???