Path to configure the MQTT broker plugin in HAOS

Good day

Can I ask for help setting up the Mosquitto broker to receive MQTT from an external source?

On a machine with OS Debian I have created a file /etc/mosquitto/conf.d/iot.conf in which there are data to connect and everything works on this machine (after entering mosquitto_sub -t '#' -v I get the data).

I’m trying to get this data in HAOS, which I run as a dedicated system on a Raspberry Pi, and the MQTT broker is installed as an add-on to HAOS. The directory /etc/mosquitto/conf.d/ did not exist, so I created it. The procedures and commands I know from the Debian OS don’t work in HAOS, so I have no way to verify a working connection. I then created a new device in configuration.yaml:

mqtt:
- number:
name: wattmeter_ch1
command_topic: n/a
state_topic: node/1/sensor/28/value
min: 0
max: 10000
step: 0.001

This shows up for me in developer tools > states, but I don’t get any data.

So I don’t know if I have a bad connection between the broker and HAOS, or if due to the absence of a directory and Mosquitto in the form of a plugin, I need to put the configuration data in another directory (or tell it where to look for it)?

I’ve found some tutorials and am reading the documentation, but as a non-english speaker some of the information is lost on me and I haven’t been able to piece it together for over a week now. Can anyone advise?