Ok, replication is one way: server->clients.
There are several things you have to do:
- Make sure both the client and the server have the corresponding inventory objects or components.
- When you add an item to the inventory make sure an RPC is called and the exact same item is added in the corresponding server inventory too. This will handle your client->server communication.
- Make sure the inventory object component is marked as replicated and all values that you’ll use are also replicated. This will handle your server->all clients communications.
Now you should be able to see your inventory on all clients.
P.S. I’m sorry but I don’t have the time to watch through the videos so I’m not really sure what your setup is.