how i can take chinese visa (z)

First, you have to find a job in China. Then ask your employer in China to provide you the work permit for foregners and Invitation of a duly authorized Chinese Unit. Next, you can apply for the China work visa from the local China Embassy or consulate with the necessary documents.

I'm sorry for the negative answer, but if your intention is teaching English then you're unlikely to be accepted due to you not being a native of an English speaking country (and your poor grammar). Try companies on the internet, type in something like, "Teaching in China" and follow the leads.