Protein is it true?

Protein cannot be converted to fat. It is just broken down into amino acids. It will not turn to fat.

Protein CAN in fact, be converted to fat.

here is a much better explanation than I can give here.

http://www.healthline.com/hlbook/nut-protein-metabolism

as to how much you can have at one sitting, well that's a much more difficult question to answer, it varies depending on the individual, how much muscle mass you have, how active you are, what KIND of activities you are engaged in, your genetic disposition, your age, your sex, you current fat level...etc. Its a very complex equation. Body builders are constantly tweaking their protein levels to achieve maximal results, some never find the "sweet spot" others do quickly. It's a bit of a game to find the perfect amount, but usually you can feel safe that anything from 18% to 30% is generally ok for most people who have moderately active lifestyles.

Excess anything can = fat