Im 16 And only weigh 60Kgs. Im very active thats probably why but

how can i put on those extra killos. Ultimately i want to wigh about 70 Kgs. Should i do this by eating junk food or do i just slowly and gradually eat more "Healthy" foods. I go Gym 3 Times a week and after wards i usually take protein shakes. Should i keep that up?

you're 16 and still growing..you have nothing to worry about in regards to your weight and body...just EAT...don't focus on calories or working out. get your regular activity in and eat what you feel like and when you feel like it...your body will be at the weight that is best for it. i wouldn't say for you to consume more junk foods because that isn't good for anyone but anything in moderation is appropriate. it's important that you allow your body to grow and develop and too much emphasis on what you're eating and trying to reach some ideal will set you up for an unhealthy relationship with food and reap negative consequences for the functioning of your body. if your weight is too low for your frame then naturally you will gain weight when you give your body adequate nutrition, but if not then you will maintain. does that make sense? i say, just listen to your body and if you want to boost your calories without really thinking about it then just buy a box of protein bars that have about 300 calories each and just eat how you normally would.

I'm not so sure about the specifics, but definitely don't eat junk food to gain the weight. Of course treats are okay occasionally, but you should focus on eating balanced, healthy meals. They should contain foods with high calories as well (as long as they're healthy), and you should be consuming more calories than you expend each day. But you probably already knew that ;]. I believe protein is good for gaining weight, and I think weight lifting is more efficient than cardio or any other exercises that burn a lot of calories when you're trying to gain weight, although someone more informed should verify that. If you haven't already, I think it would be really helpful to use some of the tools on this website or other websites to find out how many calories you should have a day. Because you're active and trying to gain weight, the number might be higher than you'd guess. It could also really help you to log your food intake and exercises every day to make sure you're consuming more than you're expending. Sorry I couldn't give more specifics! There are a lot of other people on CC who will know more than I do. But add me as a friend if you'd like and message me anytime =].

Try entering your stats into this link http://www.kidsnutrition.org/bodycomp/bmiz2.h tml which is aimed at people under 21.  60kgs is 132lbs so you can judge if you're underweight or a healthy weight.  If it does turn out that you are very underweight then you should talk to your parents and get some advice from your doctor.  You'll also be able to see from the chart how many calories you need to maintain your weight.... and it's probably higher than you think. 

If you want to gain weight there are a lot of high-calorie but healthy foods you can choose from.   Nuts, for example, are very energy-dense and also highly nutritious.  If you eat a lot of nuts and/or nut butters that will give you a lot of extra energy for very little extra bulk.  Other ideas.... avocados, red meat, full-fat dairy products, olive oils.  And then there are the starchy carbohydrates.... bread, rice, pasta, potatoes, bananas.... incredibly useful for weight-gain.  Try to get your calories from real food rather than protein shakes...

'Junk food' is a bit of misleading catch-all.  A hamburger, some pizza or a bar of chocolate isn't 'unhealthy' if it's part of a generally healthy diet with a good quantity of fruit and vegetables.  So you can enjoy those if that's what you like... just do it in moderation.

If you are female you will need at least 2500 calories sedentary, male 3000 sedentary. But if you are very active, I suggest you cut back on your exercise and eat closer to 3000+ female, 3500 male. For more info, The Aim is to Gain: Advice on Weight Gain, Whatever Your Reason