You can entrust a patent agency to help you handle it. All you have to do is tell them your idea (technical solution). The fee includes official fees and agency fees. The official fees can be reduced by applying for a 15% payment. , the agency fee generally ranges from 3,000 to 5,000, mainly depending on the type of patent you want to apply for.
You can also do it yourself, download the patent specification template from the Patent Office website, and then fill in the content. Be careful when writing claims, depending on what problem you want to solve and what conditions are needed to solve the problem. This is a technical job. As for expenses, they are just official fees. After writing it, just mail it to the Patent Office or submit it to the patent agency.