I'm guessing that since you're asking this you're under 18? -_- You don't need liposuction, you need to research natural ways to lose weight, and not try to solve your problems with expensive and unecessary surgery.
Are you overweight now or just scared to become over weight? There are so many other options you should think about at 13 before lipo sweetie!! If you are not overweight ... Do not let this consume you... Have fun, eat healthy, participate in sports at school... And you will be fine... If you are overweight the above mentioned can apply too.