I have seen everyone on BOS and my school say that Bio is a science for dummies and how it's really easy and based on rote learning etc. but I just can't seem to get any marks in it. I do really well in Economics, Chemistry, extensions maths and all the harder subjects but when it come to Bio, I feel the more work I put in the lesser mark I get. It's the only subject where I am not in the 90' but in the 70's.
I feel so stupid when I see everyone else who puts minimal effort get really good marks while I struggle to pass.
Any suggestions on how to improve in biology?
That's really a huge misconception. Don't ever rush when you're learning biology, but give yourself time to process the information especially because some concepts can be quite complex (for example protein synthesis throws a lot of people off).
When you are learning from textbooks and/or other people's notes, often you can be confused about how much you really need to know. If that happens, revisit the dot point to remind yourself what it is really asking for - and if you are unsure, you can always ask your teacher or one of us here. It's also so important to ask somebody if you don't understand something.
What I suggest you to do is - after you have learnt a certain section in a biology topic, for example, "The Blueprint of Life - Section 1", look for all related HSC past paper questions and try to answer them. Then, get a teacher/tutor/somebody here to mark it. This does a couple of things - it might allow you to discover that maybe the reason for you losing too many marks - because of insufficient knowledge; you may not be writing enough; you may not be answering the question directly or at all and just regurgitating the information; not answering the questions in the correct format/not providing examples; allows you to realise what knowledge you should have had have to answer the question.
When I was studying biology I used the textbooks Biology in Focus and Biology in Contexts (3rd Edition) in conjunction with many past students' notes (like the ones you can find on this site). Always make sure that you are using a variety of sources for your learning (some summaries may be missing a lot of information and you wont know that until you compare) and that you are doing lots of questions to supplement your learning. If you find that a textbook for a particular section/dotpoint is just too confusing, start with another that is much more simplified and revisit the first textbook later to build up your knowledge.
TLDR:
In my opinion, the following steps is what will really bump up your marks:
1. having good understanding of concepts directly answering the dot points, backed up with examples
2. application of concepts via completing questions
3. getting answers marked, reviewing feedback.
Good luck!