Fad diets like intermittent fasting or any kind of major lifestyle change like that take a lot of willpower and self-discipline, which is also why most diets fail long term.

Better thing to do is have a routine first. A lot of people don't have any eating habits, it's more of an afterthought or a "whenever I'm hungry I'll eat" kinda thing. You can't base a diet off of that.

If you fix your diet by just eating at the same moments, roughly the same amount of time, only then do you have a baseline. Then make tweaks on that baseline. Evolution instead of revolution, only that will be sustainable.