So you want to change the world but don't know where to start. How bout joining the United Nations Youth Australia. According to their website, "UN Youth Australia is run entirely by a team of over 1,000 extremely dedicated volunteers, all aged 16-25. We are one of the only organisations brave enough to empower young people with skills in education, in design, in leadership, in organisation, in diplomacy and in negotiation to execute their vision."
If you'd like to find out more, check out their website https://unyouth.org.auunyouth.org.au.