Australian laws for dropping out of high school?

I know it's bad to drop out of highschool I know :/ so please no lectures, I have my reasons & I know I can do my HSC in tafe, Im in year 9 currently & want an apprentiship to be an electrician, I want to know when I can drop out If I get one, I struggle at school qnd have changed highschool before, my social life is falling apart & I also have social anxiety and depression, which doesn't help either, thankyou xo