Unless things have changed a lot, you do chemistry , physics, mathematics and biology all year. whether that 2 x semester courses or 1x whole year course depending in the uni. They were pretty much all the same for everyone, although you can do easier courses if you don't need that subject for anything in later years. So if you are majoring in a biology subject, you might not do physics 101 but instead do physics for life sciences.
In my experience they assume you've done physics, chemistry and 2 unit maths in the hsc, but the biology started from year 10 knowledge.
I think you have a bit more flexibility these days ie able to do some second year electives in first year but I'm sure most people follow the standard pattern.