MQTT node- device username

So you mean I have to send the data to broker and then split my data and feed it to my devices or I also can split the data based on the topic and the devices should subscribe to the topics. The problem is that I'd rather use node-red on the other side as well but the one that I have on that side is basic and I think it can't support splitting the data. I'll double check to find a better solution.
Thank you