It's impossible. 吸血鬼 are complete myth. People who think otherwise are completely messed in the head.
Even if they were real (Though they ARE NOT)I don't see the fun in being one. Living forever is eternal despair. There is nothing cool 或者 fun about it. Living while the ones 你 care about get old and die right in front of you. Hunting is the only thing 你 can do; 你 don't even have the pleasures of enjoying the simple things: Food, water, sunlight, and being around others. It will slowly drive anything mad.
It's a stupid thing to want to become. But really, vampires do not exist.
Stay in school and build a life. All 你 can do is look forward.