Hello!
As Quantum44 said, a raw 30 in Chem as well as a raw 30 in English is a prerequisite.
It's definitely a HUGE plus if you do VCE Biology!!! A lot of the stuff that's covered in the syllabus comes up in what we're learning (e.g. cell organelles, cellular respiration, immunity, recombinant technology). Quite a few people in my cohort who didn't do Biology have it a bit rough with the extra workload and content to understand.
For Monash med, we have a subject called 'Medicine of the Mind' and it overlaps with a bit of VCE Psychology (particularly operant and classical conditioning). I found doing VCE Psychology helped me with understanding one of our lectures.
If you're aiming for med, I suggest you try out for interstate unis too!! Other unis have Methods as one of their prereqs, such as James Cook as far as I'm aware.