Hunger scale or fasting?

I’ve heard some advice around fasting and allowing hunger if it’s not time to eat. And also, have how much you plan to eat as part of your protocol (4oz protein, 8oz veg). Then use things like bone broth or fat bomb to help with hunger if needed.

I’ve also heard to eat using -2 to +2 on hunger scale.

Are these two different tactics to try or all the same?