If you are in Beijing, you can send the application documents to the reception desk of China National Intellectual Property Administration Patent Office, No.6, West Tucheng Road, Jimenqiao, Haidian District, Beijing. The postal code is 100088, and the patent application reception consultation is 0 10-62085500. If it is local, it can be submitted to the local agency of China National Intellectual Property Administration Patent Office; You can also send a patent application to the above departments by registered mail. Another national defense patent branch specializes in accepting national defense patent applications.
Special reminder, don't think about saving money when applying for a patent, otherwise it is easy to lose big because of small. Ask a professional to help you read or even write the application documents, and be serious!