How can i gain muscle mass and loose weight?!

We had this fat tester thing at school
My BMI is % 22
Healthy BMI is from 16 - 26

Im 15 years old
Im 160 lbs
Im 5'10

I want to loose weight but gain muscle

I just bought Muscle Milk to help me gain alot of muscle mass!.
I will be lifting hard 5 days a week for 6 weeks!.
I THINK this will help me gain muscle mass, how about you!?

I'm completely cutting junk food and pop out of my diet!.
The only thing i will be drinking for 30 days is water!.
I'll probably keep having 3 meals a day because I cant afford protien bars and things though so, ill have

- Morning; Cereal
- Lunch; Good lunch with a lot of protien
- Supper; Nice super with lots of protein

My questions are

- Can I do cardio after my workout to loose fat while trying to gain muscle mass!?

- Should i take my milk before or after my workout!. [[ IM ONLY TAKING ONE SHAKE A DAY]]

- Any other good advice would be GREATLY appreciatedWww@Answer-Health@Com

---

---