What kind of invention can be patented, where can I apply for a patent, and only theory can apply for a patent?

As long as what you invent is novel and creative, it is a whole scheme! If it is an invention or method that has never been used before, you can apply for an invention patent, if it is a structural improvement, you can apply for a new patent, if it is a design, you can apply for an appearance patent, as long as you can apply for a theoretical patent, you can guarantee that it is a complete set of programs! To apply for a patent, you can apply to the Intellectual Property Office yourself, or you can apply to a local agency to find an agent.