workout is necessary to stay healthy and fit....it's better to have trainer or coach in-case you are unable to make it on your own....besides exercise and all that diet is very important.... your diet needs to be balanced...here are some important tips to stay fit

1 Eliminate your sleep debt (sleeping hours should be 4 to 5)
2 Drink more milk (make your body to consume more calcium)
3 Eat more fruit and veg (u better prefer fruits and veg instead of meat)
4 Try new activities(indulge yourself in extracurricular activities)
5 Have a hearty breakfast (don't start your day with half empty stomach)   
6 Let Your body sweat ( Do any kinda physical effort if not exercising)