How can I get a two pack?

FoxButtox
I want to get a two pack and I don't care how long it takes, I just want one. I am a 13 y/o girl, 5'4", 125-130 lbs. I play basketball but our season is almost over for school and we don't have the money for me to do any other sport right now. I just need some advice on what I should eat and how I should exercise.
(P. S. when I stretch, I can see the line in the middle of my stomach, but when I go back to my normal stance, I only have a little bit of fat covering my abdomin.)
How can I get a two pack?
3 Opinion