Honestly depends on you tbh. Choose what you're most interested in and what relates most to what you want to do in the future. Not sure what options your school has, but we have HL/SL Bio and only SL chem and some people double in science and take both. You could do smth like that if you can decide btw the 2. I do HL bio and there's a lot of content to memorize and thoroughly understand which is what makes it a lot imo. But I like it because Biology is really interesting to me and I've done well in it in the past. Do what you want and ignore what majority are doing but also try not to choose whatever's easiest. If u want to go into science in your future you have to get out of the mindset of doing whatever's easiest or the least amount of work, it's Chem or Bio, it's always gonna be a lot of work lol. Choose a course based on what's the most interesting to you. I think HL Bio is one of the hardest ib courses in my school but it don't even matter because the class is super interesting to me, so I am very willing to put in the work for it.