I can usually get to C/D in contests. However, I often get stuck at As for overestimating its complexity.
Apart from this, I code really slow and buggy at A, but code way better at Cs and Ds
So what should I do to solve this interesting problem of me?
I clicked on your contest history and looked at your past 10 contests. It looks like you typically solve A faster than any other problem, and don't have more wrong submissions on A than other problems.
Can you explain why you think you are better at C/D than A?
It's a generic thing, including virtual participation, school training, etc.
Basically I can't grasp the point of simple problems quick enough.