How are you activating the lights? Or are you hoping the Sonos app will do it for you? (It won’t, by the way.)

Manual, with a switch. No, I dont hope that the app will do it, but when I «start» the speaker, I want the lights to be activated, from a signal or something that tells the light to turn on. 

I’d likely be looking at ITTT as an option, but as @nik9669a states, Sonos doesn’t externalize a signal to tell anything other than its own controller that it is on.

Thank you

There are ways to do this by using smart home functionality. Home Assistant or Hubitat are two systems that I use that can see output to a Sonos device as a trigger for a rule to fire and turn the lights on. But it will be a lot of work/learning/cost if this is it's only use.