This is surprisingly easy. Unless you have some medical condition, in which case it may be impossible. ~2 years ago I was 110 kilos, 185cm. Borderline obese. Now I'm in the upper 60's. The 6(8 turns out in my case) packs became a thing only as a consequence of the wfh, and subsequently boredom and eventually "let's see if it's possible". Realistically it took me about a month. And while exercise played a role, most of it came from food. Without starving at all either.
Science solved this problem way before the shake weight.
Understanding some basic concepts in nutrition/wellness, such as macros and micros, calories, how Energy Expenditure (keeping you alive, walks, lifting weights, etc) and Energy Storage (Fat, Muscle, etc) all ties in with your unique genetics, body composition and lifestyle goes a long way.
Quick and dirty trick: be at a low Body Fat Percentage and have abdominal muscles (which we all do ha).
Skipping meals doesn't help you lose weight in most cases. Your body optimizes for the expectation of not having food and stores more energy.
Eating smaller, filling meals helps more. I actually don't know of anyone who's lost weight from salads. Usually they're just left feeling hungry and usually add dressing to compensate (which just gives you completely unfilling calories).
