«Home trainer contrôlable

must I couple «Home trainer contrôlable with a wahoo kicker ?
What is the difference with or without this

I’m not sure I fully understand your question, but if your home trainer is a Wahoo Kickr then you can pair it as controllable (as well as Power Source). If you don’t pair it as controllable then Zwift will not automatically adjust the trainer resistance according to the terrain (when in SIM mode) or the desired power output (when in ERG mode).