I suggest you go to China National Intellectual Property Administration or the Intellectual Property Office of Liaoning Province to check the directory of regular patent agencies in Liaoning Province and Shenyang City.
Of course, in reality, there will also be some foreign agencies' agency companies and intellectual property companies without formal agency qualifications who will also do patent agency business.
The specific income is related to my ability, because patent agents usually get a commission by piece, that is, if you can do more, you will get more income if you have old customers.