as I can´t find an answer, i hope to get some help here.
I´m using Node-RED to switch some GPIOs of an EPS32 and to visualize some values (temperature, humidity) in the Node-RED-Dashboard. Works well.
Now I have to visualize theese things in an Excel-Dashboard, which runs in a private network. So the states und values must be taken from Node-RED via http, I think, and be put in Excel.
Initially do not worry about node red. Initially you need to work out the details of how to show a value in that dashboard. If it is possible using some http interface then you need to know the details. Once you know that then we can help implement it in node red.
The Dashboard in the other network is administrated by myself. It uses a lot VBA for Excel to show values of many different systems. Also from this dashboard some functions of systems can be controlled.
So I think, there a lot of possibilities.
I thougt about a something like the "http response" as it is shown in the example with the "Hello-json".
At the moment it would be the easiest way to send http-request and get back a value (like 0 or 1 for off or on).