What kind of printing machine has high salary?

I have studied flexographic printing for four years, and now I can start it independently. I found that the position of flexographic printing captain is really rare and the salary is not satisfactory. Now I want to learn to operate other machines and find a printing machine with high salary. I hope my classmates will give me advice not to copy. I'd better be the captain of the printing machine to answer my questions. The question is as follows: 1. What printing machine is better to learn? 2. I want to find a company with several kinds of printing presses, all of which have high wages. I am now in Minhang, Shanghai, and I certainly hope to find a job like this nearby. I want to find a deputy with a monthly salary of about 3500. If I learn to be a captain, I hope the captain can have a job of more than 8000 yuan. This is my goal. I hope that after learning this printing machine, such a job is not difficult to find.