MY FRIEND LOST 30 POUNDS IN A MONTH ! 10 POINTS?

Okay s she was 5'6 130 pounds now she 100 pounds & her dr. said that her body is healthy ! & she worked out daily .. So I'm going to do the same thing, I'm 5'6 & 216 pounds & I want to be at least 180-190 pounds before august 15th ! should i workout twice a day? & how long should I run on a treadmill? NO walking , RUNNING & How can I lost back rolls and neck rolls? oh & I'm 15 . positive comments ONLY thankss(: