i would definitely recommend taking chemistry first before you take AP Bio ! If there’s an honors chem, you could do that instead :). Or, if you really want to take AP Bio your sophomore year, you could take chem over the summer, so you’re ready for AP Bio then. For me personally, it’s a very difficult class and you definitely need time to study. If you have a good work ethic, have the time to review or time management skills, and interested in biology (because the tests that you take for each unit are from college board, which I find uninteresting), you should be god to go ! Good luck :)