so my summer break starts next monday & ive made it my goal to lose weight over summer - my summer break is 2 months long. im currently 120 lbs and 5 feet 11⁄32 inches tall i wanna lose about 10 to 15lbs (im 13) . How can i lose this weight in a healthy way and then keep it off? the parts of my body that concern me the most are my lower abdomen and thighs. thank you in advance xx :)