Main thing is your diet (The things you eat) Try to educate yourself with food. You can by posting up questions or doing some reading on it.
Just diet alone will help you lose a ton. Of course excerise is always a good thing to add with it.
Start out with a walk/jog/swim or any cardio/body movements.
Then work your way on to weights and different types of workouts.
Diet... some stuff you should consider. There are lots more but i'm just giving you some examples.
Whole grain breads, pasta, pita or wrap
Cream of wheat
Low fat cottage cheese
Flax & Fish oil
Fruits & Veggies (Carbs)
Strawberries:Raspberries: Blackberries: Blueberries: Banana: Apple: Pear: Grapefruit: Peach: Orange.
Peppers: Onion: Tomato: Squash: Peas: Carrots: Green beans: Broccoli/cauliflower: Leafy greens: Asparagus: Lentils: Cucumber: Celery.
If you can replace Soda with Water... DO IT!!!!