how to build the confidence?in other words,how to make self not too shy?tk

Camaha is an idiot.
Give everything a go regardless of what you think the outcome may be; through experience comes growth.
Don't listen to those that belittle you; I understand Chinese parents are particularly good at this.You know what you're capable of.
Disregard what others think about you; you have a one-in-one-point-three-billion chance of ever seeing them again.
and get out of China as soon as you can; it's an awful place for someone of little confidence as people are very,very unforgiving and narrow-minded.
p.s.Don't dress like a whore,don't wear those stupid-looking "glasses" with no lens；they do nothing for your confidence and only serve to make you a shallow person.