To control tado° devices using Amazon Alexa, you’ll need to add the tado° Skill to the Amazon Alexa app.
To do so, follow these steps in the Amazon Alexa app:
Select Skills from the menu.
Search for tado° and
activate the skill by selecting Enable to Use.
Sign in to your tado° account and accept the conditions.
Learn more about this in the Alexa Smart Home section of the Amazon Help Center.