The best advice i could give is follow the subject guides. For example in Biology, don’t focus on one book, read at least two and try to cover all the points mentioned in guide(don’t forget AHLs). Look through the past papers and question banks - they will help you to see if you understood what you’ve read. Same goes with chemistry, really. At first it may seem hard, but it will be really rewarding at the end! Just form your study habits from the beginning of IBDP and you’ll get used to the workload. Also, choose an interesting topic for your EE that you would like to spend a lot of time on, because if you choose a boring one (like I did), you will find it really difficult to write it, correct it etc., especially bc ee requires a lot of background reading. so don’t rush with that! Also, try to do as much as you can during the summer (not many do, so don’t worry).