You’re right to a point @Lueloff. But you can’t expect to consume unlimited energy and also burn fat.
The point is that as you become fat adapted your body will become more adept at burning stored fat for energy. As you rely more on body fat for energy your hunger decreases. As your hunger decreases it takes less dietary fat to reach satiety.
It takes a certain amount of energy to function. Energy basically = calories. Those calories can come from what you put on your plate, you body reserves, or most likely from some combination of both.