Studying for higher human biology (SQA)

The final exam is on the 27th and I have no idea how to study effectively to ensure that I know all the knowledge. I feel quite overwhelmed with the volume of content and I don’t know how to overcome that fear.
I also struggle with having the right exam technique in tests even if I know all the content which loses me quite a lot of markers. It’s the same with the math problem solving question, math has always been my strong suit but those questions still stump me .
So if anyone has any advice and study techniques it’d be much appreciated. I think it’s also important to share I’m really aiming for an A to get into medicine but I also wanna strive to get an A1 which I know I can do if I study effectively 😭