Is just fitness suitable for protein powder?

Answer first, no need.

The amount and intensity of exercise for beginners seem to be relatively small, so protein and protein, as a kind of energy, will accumulate in your body in the form of fat, which is not conducive to shaping your figure. And it will give you a psychological contrast. The more you practice, the worse your body shape will be, which will lead to a decline in your enthusiasm for sports.

So novices don't need to eat protein powder, they just need to train according to the normal exercise prescription. When one day you find that you can't grow muscles without adding extra protein, go and eat protein powder.

It is unscientific for many people to measure a novice's future figure by his fatness. First of all, there is no mutual transformation between fat and muscle. It's not that I'm fat and have a lot of fat, but that I can become lean meat after practicing. This is a pseudoscientific fantasy. The only scientific way to gain muscle is to stimulate muscle with a certain intensity and increase the circumference and quantity of muscle fibers. So don't listen to their nonsense, arrange recipes according to your own training volume, and it is certain to eat more than usual.