How to get a washboard stomach ?

hey i am a 17 year old boy i weigh 154 pounds and am 170 cms tall . how should i lose 5 kgs as quickly as possible and how much time would it take ? also i would like to have a diet suggestion as to what i should have for breakfast lunch and dinner and is eating fruits good enough ? How many hours a week should i go to the gym (treadmill) and what all should i do in the gym ? I have a really hectic schedule so yeah i hardly get time but still . Please help me as i am really desperate because i have seen people in my school who were really fat and had the fatness in their genes defying the genes and becoming thin and tall ....