I want to do ground maintenance for China Eastern Airlines. What are the requirements?

Not sure what you mean by repair? Aircraft, or anything else, if you are doing maintenance (aircraft maintenance), you need professional talents. This department is roughly divided into electronics, on-board (usually cabin equipment) and engine departments. If you are doing other ground maintenance, then you need another department. Other than that, it is relatively easy to get into because the academic requirements are not high, and the airlines have information departments that deal with computers!