Status feedback to HA

With the inside temperature I switch my USB fan on and off, which works. But now I would like to report the status on / off to HA and display it. I’ve tried everything, but nothing that works. Which nodes do I have to use so that this is shown to me.

You could use the entity node as a binary sensor or the API node with the POST /api/states/<entity_id>

I’ve tried everything possible now, but I don’t get any feedback on HA. Maybe my settings are wrong too. The feedback to HA is only made the first time it is created. After that, the value does not change any more. Do I have to adjust anything else? The missing API.