You should ask your biology teacher if the year 11 is content which you will need, their answer will essentially be yes, this is because a core focus of the content you are doing in year 11 (alongside the modules and incorporated into the modules) is a combination of foundations and "Working Scientifically" [NESA syllabus codes BIO11/12-1 to BIO11/12-7].
Questions focused on BIO11/12-1 to BIO11/12-7 are actually quite common in the HSC exams, if you look at the 2022 HSC Biology Mapping grid from any of the current release of past exams you will find this.
As I stated earlier "It is usually the case that the exams are more heavily concentrated with content from the year 12 curriculum".
If you need proof, a good example is Q32 in the 2022 HSC paper which the HSC markers state requires you to "Demonstrates extensive knowledge and understanding of processes that could lead to differences in the gene pools of different populations, including mutation, gene flow, genetic drift and natural selection" in order to achieve full marks. Remembering that natural selection is covered in year 11 module 3, and mutation, gene flow, genetic drift come from year 12 module 6.