Question

what food 15 years boy should eat

Answer 1

15 years boys should avoid taking junk food from at this age itself so it can prevent problems in future
 he should take healthy food such as spourts seeds,green-leafy vegetables,...

Answer 2

The adolescence starts at this age so every person should have a balanced diet shuch that all the nutrients are sufficiently supplied to the body.
Our balanced diet should atleast contain proteins (pulses,meat) carbohydrates,fats/lipids (Generally available in all vegetables)
More amounts of water should be consumed.