hi! i finished my ocr biology course this year and you’re 100% correct about the mark schemes because they’re BRUTAL at points, but you do need to make sure you know all of the content too. the best thing you can do is improve exam technique, so being able to pick out what part of the spec is being tested in a question and answering it directly etc. studywise is a website that has a write-up of the spec and the answers to most of the points, so for questions where you need to give a straightforward definition, you can memorise it word for word. studymind is another website and it was the most helpful thing for me, they’ve collected all the questions in past papers and categorised them by topic, so it’s easier to focus on one if you struggle with it more. you’ve got this! biology can get very hard at times but you can do it!