Are a lot for the six pack shortcuts a scam?

No, ALL of them are a scam. Also pretty much any marketing material that refers to "shortcuts" or "secrets" is a scam.

If you want six-pack abs then you need to do a lot of cardio, minimum of an hour a day 6 days a week. You need a calorie controlled diet extremly low in carbs but with varied sources if protein and healthy fats. Thirdly (and least importantly) you need to do abdominal excercises, various sit-ups and planks.

Measure your body fat percentage to track progress (10% is your target).

There is no shortcut.

Note: none of this involves paying any money for any gizmo or plan.
Is 'All in One' a good reference book for CBSE class 10 math and science?

The answer depends upon your understanding and hardwork that you're ready to put in. You can go for the book which you've mentioned or any of the books available in the market offering more or less the same content. You can go for the classic NCERT textbooks and exemplar problems or RD Sharma or RS Aggarwal or ML

What are some simple weight-lifting workouts?

Nothing is simple these days!It's information overload.Just type any keyword related to weight lifting, and you will have millions of results in just few seconds.Every website is promoting something different.Some say, a high-volume light moderate weights are best to build muscle and lose fat some say its the exact opposite.A website created by a calisthenics lover