I wnat to learn some fighting Techniques?

As said previously try to ignore the other persons ignorance. No sense in making your life tough for some idiot with something to prove. That being said, Nothing is better than actual training under proper supervision(because you did say your only 13). You'll want to explore schools that train in self defense,not a sport school. THERE IS A DIFFERENCE. A good school will train you in ALL phases of combat training. But also teach you when to use it, and how to use it. Any time you engage in combat out in street or school or what have you. You are also responsible for your actions. In other words if he points his finger into your chest and swears at you, and you then decied to dislocate his elbow. That can be considered EXTREME USE OF FORCE and then you parents are liable for YOUR actions. Meaning they can be sued in court. It is one thing to know how to defend yourself, its more important to when and to use the APPROPRIATE amount of force without getting yourself into further trouble.