Can I lose weight by doing the following?!

Can I lose weight by doing the following?

I'm 17 and I weigh 315lbs. My dream and goal is to become a Model, Fashion Designer and a Pastry Chef(maybe). I went to my nutritionist about two days ago and she said do what makes me feel good. So far, I've lost 13lbs and I feel great.

I love to Walk both Indoors and Outdoors. I love walking. If I indoor walk every day for 4 Miles plus eat healthy, will I lose anymore weight? I eat the following everyday.

B-Old Fashioned Oatmeal w/ Raisins
L-Half Turkey Sandwich, Spring Mixed Salad w/ lots of veggies.
D-Boneless Skinless Chicken Breast w/ a Salad or Veggies

and my snacks are fruits and veggies. I drink lots of water every day. I don't eat Junk Food or Sodas.

Yes, if you excersise and eat healthy then you will loose weight. You have to understand though that there will be a limit to how much weight you loose and when you reach that limit you'll have to step up your excercise routine if you want to loose more.