Since you're only 14 I'm guessing you don't have much muscle. So to 'tone up' you need to first gain some muscle, than loose fat gained. It's hard to loose fat while bulking up, because to get a lot of muscle, you need to eat a lot of food.
What I would recommend is this:
Eat about 5-8 good meals a day, try and make them as lean as possible. But make sure you get a lot more protein and calories into your diet. To find out more about this search the forum.
Workout. Do 8-12 reps, and you will gain mass this way. Find specific exersizes, and how much to lift in other posts.
When you've gotten the desired amount of muscle, you will need to start 'cutting'. Cutting means loosing fat that you've gained. You will need to cut down on cals, but not too low. Eat the same amount or more of cals someone your age should be eating.
When you've lost the fat, your body will be 'toned'. From what I have read all tonning means is having your muscles look more defined. To make them more defined you need to loose the fat that builds up over top of them.
Hope that helps.