CCA is not as important as your grades. If you think you cannot
cope, focusing more on your grades would be a better choice. But at
least join something that wont take up much of your time and even
better if it allows you to have some leadership position. If your
grades are excellent, even if you have crappy CCA performance
they'll still take you in. Rmb, they look at grades first! If
you're aiming for all B's its very dangerous, trust me. There are
many people with pretty good grades like AABB or ABBB. Aim higher
and youll do well. Just start studying from J1 dont wait until last
min again, all hard work will pay off.