How to lose weight and gain muscular body fast and without dieting?

Not possible: That is not possible. Otherwise, the whole world would be doing it. You can exercise all day long but if you're not getting the right nutrients and proteins, you won't be able to build muscle and recover after each workout.

Depends: Depends upon you unique genetics. But, in general, get enough lean whey protein to support your weight (resistance) training, decrease sugar and refined carbs. To get the quickest results maybe you should start out with a personal trainer.