The Verdict: Need More Info
Your passport puts you on the Work and Holiday visa (subclass 462), which may need a letter of support from your government. Check your country's requirements and annual cap on the Home Affairs website first.
Depending on your nationality, the 462 can require a set level of education, functional English, and a letter of support from your own government. Several countries have a capped number of places each year, which can run out.
Age is tested when you lodge, not when you travel, so if you are close to your limit, lodging is what stops the clock.
Specified work in defined regional industries unlocks a second and third year. The visa does not lead to citizenship, but Australian work experience can count towards the points-tested skilled visas.