Gosh, you've done well to have the choice. A few weeks ago you were living with your parents after an internship and had no job. Whatever you choose to do would be impressive.
;)
As you are only 12 years old you have plenty of time to think about it while you focus on your studies and try to deal with that annoying friend who pretends to like you.
Concentrate on doing your best at school and decide when you have achieved the best grades you can.....you may well have changed your mind by the time you are old enough to think about university courses/job applications