help pls

in year 13, doing chem bio and maths for alevels. now im actually sick of school and im so behind. when i say im behind im like 5 whole chapters behind in every lesson. and on top of that they expect me to do AS revision as well. they make us learn the topic ourselves at home so when we go class its exam style questions straight away. i have teachers who teach fast, too fast and literally go throught a whole big chapter in one lesson. i have teachers who give me 5 tasks for homework which is very time consuming and doesnt really help. and even though im home after school all the time and never go out im always studying. but all these tasks and homework just dont fit in my table table.