Ok so i wanna be at120 llbs?

im 5'5'' and 135. i play bball for about 5 hrs every week. also, i play softball in the spring also for about 5 hrs a week. 2 times a week i have PE for 1 hr. how long will it take me to get to 120 llbs.? any other tips. i dont wanna make it known (ex: dieting, gym) since im only a teen