From the Alexa app, you can control your setup device by device.
With Amazon Alexa voice assistant, you can also perform these actions by voice:
Ask "Alexa, what is the temperature of the living room" or "Alexa, set the bathroom to 22 degrees" or "Alexa, decrease the temperature of the bedroom".
You can also command your setup as a whole. So try "Alexa, increase the temperature by 2 degrees."