Hi we are planing to visit china as a family and i want to have plastic surgery in china.

I have never been to china and i already bought flight ticket but duration is 3 month , but i don't thing we will stay that long it is just in case ... and we can always change booking so what do we need to apply for visa?? I only have australian passport but in information it says if u are first time applicant u need your previous passport ..i don't get it what previous passport ?? I only got australian passport .. please explain