No, I don’t use Homey myself. But you this is basic understanding of how Homey (and all smarthome controllers in general) work and not really related to the Shelly app. You should read the manual first.
Or perhaps someone else is willing to explain these basics to you.
A small tip, your flow should start with the ”temperature has changed" trigger card. There is a token on the card with the changed value allowing you to interact with and perform the action you want (which is still not clear to me).
