How does Graduation work in Australia

I'm not too sure if I need to apply for it myself or the university applies for me?

I'm finishing all my units by the end of this year (2nd Semester 2026) and was wondering if I'm able to graduate in December 2026? I used to be from Malaysian campus and have tons of friends that finish their units end of last year (2nd Semester 2025) but are only graduating this April 2026? Just curious why the Malaysian campus doesn't provide the same dates.