CARBS.---
You need these for energy and during intense workout. These are your brains food. But, don't over do these because they can slow your metabolism. Eat most of your carbs with breakfast.
PROTEIN---
These are essential for building muscle. You need 1 gram of protein for every pound of muscular body weight just to maintain muscle, you need to consume more than your weight to gain it. But be careful here to, don't sit down and eat a huge meat meal that contains 50 or so grams of protein because your body can only digest 30 grams every three hours. Anything more than that, well you guessed it, it turns into fat.
FRUITS AND VEGETABLES---
These are good for you, they contain vitamins, fibers,and essential amino acids. But again be careful here for they do contain carbs.