Multiplayer scripts behaviour | Question

Hai yall, i am making a 3D muiltiplayer game and I am kidna lost.

Honestly, I readed the whole documentation for the multiplayer and there is not explained server/client architecture.

Some 3rd party guides are making their server and client combined, some of them does have a separated project for client and server (I making a game with dedicated game server but still i would prefer to have a combined architecture.).

But in server/client combined scenario: I dont know which function is going to called on server, which by client and which by both. Kinda lost on this. The official guide does not have any diagram/documentation.

Is there any documentation official or unofficial where is the multiplayer/client script behaviour explained more clearly?

Thank you a lot!