What do you want to say?
1. If the things you produce and sell infringe his patent rights, it will definitely not work. Whether your product infringes his patent rights, you should read his authorization text to confirm your product. Are they within his protection?
2. If you think his patent is suspected of plagiarism, you can go to the Patent Reexamination Board to invalidate his patent, but you must submit relevant evidence. The invalidated patent will be invalid from the beginning. After it is invalid, there will be no infringement issue. But are you infringing the patent rights of the patent he allegedly copied?
3. If you sell the product for which you are applying for a patent before the application date, this is a disclosure of use. Others can submit relevant information during your application process, and your application will not be authorized; if no one submits , even if it is authorized, others can invalidate your patent based on this article.
I hope you can understand and don't be clever.