What's the difference between international patents and domestic patents?

A product that has not been made does not mean that you cannot apply for a patent. In fact, as long as your technical concept is mature, you should apply. If it is improved in the actual production in the future, you can take the initiative to propose amendments to the patent documents to the Patent Office (but only during the application period). It's too late to apply when you get to the market. Don't be occupied by others yet! When you apply for a patent, you don't have to apply both at home and abroad. It depends on whether your product will face the market in the future. If it is a domestic market, you can only apply for a domestic one. If you want to be domestic and Canadian, you can apply for Canadian. If you want to sell in many countries, you can apply for PCT. But before applying for an international patent, you must also apply for a domestic patent.