[BEGINNER] zigbee - how to know the commands code and cluster for any device ?

Hi, I'm a real beginner into the IoT world. Maybe it's not the best place to ask my question, but I was unable to find any answer to my question after days of researches, so maybe someone here will be an expert and have an answer for me. I'm here to learn, so don't hesitate to go deep and technical into the details.

I'm using tasmota on a zigbee gateway and it works perfectly. All devices are connected to my gateway, and displayed on the main menu. The "common" devices (like temperature sensors) displays properly their "common" properties (like: temperature, humidity, etc.).

However, it become far more complex and unclear when we have to deal with "unknown" devices. I've bought an UFO-R11 and with Zigbee2MQTT we have to send "learn_ir_code":"ON", in another hand, with tasmota we have to do the thing by ourselves (and this is what I want, remember, I'm here to learn). So, I think I have to ZbSend something:

 ZbSend { "Device":"0x5175", "Endpoint":"0x01", "Send": "e004!02" }

However, this is where I'm stuck: how may I get the values for Endpoint, <cluster>, <cmd>, and <bytes> ?

I searched for "learn_ir_code" everywhere, and the closest to an answser I found is there https://github.com/Koenkk/zigbee-herdsman-converters/blob/f83254ca55f890514744a5902edbebf8d998307d/src/lib/zosung.ts#L250, but it doesn't help. So at this point I'm stuck.

How others, reverse engineered such devices ? Is there documentation somewhere about all the zigbee command for any device (I checked the zigbee lib spec, but it doesn't help) ? Is there "hack" devices able to get such codes ?

Thanks in advance to all the people which will help me 😊

Start with the linked Tasmota Zigbee “sending device commands” documentation and the UFO-R11 page on Zigbee2MQTT; compare the documented ZbSend fields with the device information described in the issue. Done would be a clear, reproducible explanation of how to identify the endpoint, cluster, command, and byte values for this device.