Game design

Starting from the point of view, Hacking doesn't requires eligibility of academics. Hacking is just a skill which requires, Coding Knowledge, Network Knowledge, Server side Scripting Knowledge, Computer Hardware Knowledge and Testing Knowledge. Coming to the part, if you saw the articles, the children are around 5-11 years of age are hacking networks, finding zero day flaws in software etc. So, this shows hacking doesn't require any academic courses. Learning hacking through any certification such as EC - Council CEH, (ISC) 2s CISSP, CISA and CISM from ISACA and OSCP from Offensive Security will improve the professional skills of hacking. Ethical hacking: http://www.gangte.net/2014/03/how-to-become-a-hacker.html
For Game designing:
It's good that you are starting, when you are young. The first thing is that you should know what game design is actually about. You can read the book "The Art of Game Design" by Jesse Shell. If you are really think that this what you want to do then read on. Otherwise check out other fields in gaming such as art and programming. Learn some basic coding, preferably in C+. Also get hold of a game development suite such as Game Maker, Unity or Cocos2D. I personally use Unity because of their great asset store and user community. Start making games on these platforms. They should be simple enough! Don't go off thinking that I have this great idea for a super game that will make millions and start off biting more off than you can chew. This kind of attitude would portray you as a quintessential amateur gamer. Also start paying close attention to the mechanics of every game you play, whether it be on mobile, tablet, PC or console. Question everything that you come across - how is the combat system designed, why are the rewards structured as such. Etc.