Stretch marks, I need HELP fast!?

I am 13, and I have a " very curvy body figer " have dark red/purple stretch marks on my hips, from them being more large, and little light and pink ones ALL over my legs, I am sick of it! I need help, on July 15th I am going to a Quince, ( sweet 16 ) and I want to wear a short dress for a goal to weight loss ( FINALLY! ) I have stretch marks on back part behind my knees, and up wards, I wanna a smooth looking look since they are light and will probally fade fast, any fast fading reccomendation girls? (: