Ask your parents. There is no way I would personally let my kid have a WRX as a first car.
For one thing, a first car usually gets trashed. For another, they are too fast for an inexperienced driver. A faster car will get you into trouble and you won't have the experience to get out of it or anticipate it.
As for the cost. I had a friend who had a son who got a WRX after he had been driving a few years. It was a fairly nice car, under 100,000 miles, and it nickle and dimed him to death. He eventually sold it, to get out from under it.
If you had thousands in the bank, you could probably swing it.