Do I really need to fill out a w9 form to earn money from my game, I already hooked it upto paypal but in order to make  $ do I need to make a w9 form, I'm under 18 or have a job so I don't pay taxes. Is this needed?

you can be claim as an  dependent by your parents but  if you go over    $1,100 + $350 you do owe taxes. Many like me dont go over $1,450 in selling games but rarely in some cases we do. You still have to fill the W9 but your parents will be filling in the 1099 paperwork. It is almost new years so you have an entire year until you worry about taxes.