Welcome to the group, Briana. In the US there is no age requirement to be a student pilot...but no matter how well you do and how quickly you may progress, your instructor cannot sign you off to solo until you're 16. For this reason many young people wait till they're about 15 to start their lessons. Otherwise if you start lessons now, at age 12 or 13, and you become skillful enough to solo, you would end up having to still fly with your instructor (and paying for his time) for 3 years, in order to keep your skills current. Your other option would be simply to stop flying at that point and returning to school shortly before your 16th birthday for a "refresher" course.
I am not aware of the laws where you are now, in Australia. Maybe there you can solo when you're ready to regardless of age. If that's the case then go for it! Even if the certificate you get there would not be valid here at least you'll be able to fly there and become very skillful.

I have another question. I'm starting to think and look at college. I'm looking for a college or university with regular courses and also an aviation couse I could take in the future. If any one know of one in the California aream please reply.
Briana