If you can resist the urge to play computers then yes. Otherwise no. There are many things only your teachers can tell you, and you wouldn't learn just from textbooks. Your teachers know what is needed and what is not for exams, so they set you appropriate work. Generally the students who studies at home are 1.Their parents are well qualified and can teach them full time. 2.They are best students in the country and going to school is just a waste of time.
There's is a reason why most schools want students getting at least 3C's before A2. This is because students getting less than C's generally can't get offers. Good unis would instantly reject you and have to fight for places in poor unis. Redoing a year gives you a better shot getting decent unis and it's worth it