Yes you are allowed to work. but with restriction. You cannot work until you have commenced your course in Australia. Once your course has commenced you are permitted to work a maximum of 40 hours per fortnight (every two weeks) when your course is in session, and unlimited hours when your course is not in session.
Check mo other threads, may mga thread about students who are working here sa pinoyau.info đŸ™‚
or check this
https://www.border.gov.au/Trav/Stud/More/Work-conditions-for-Student-visa-holders