there are a lot of videos showing you how to setup multiplayer.
what is tricky to do is to
- setup prediction.
- add action delays with animations. use them to reduce prediction requirements.
- get moving platforms working.
the problem with the approach of most people that is that they want to go step by step because they don't understand how things work.
but you need to design the whole thing from the ground up based on your requirements.
also, anyone that wants to pay good for something puts a price and method of payment with clear requirements. anyone that isn't planning to pay just wants free advice from someone that thinks they're getting paid.