I think a new product is very good and I want to apply for a patent. Do you need the approval of the manufacturer to apply for a patent for appearance?

Morally speaking, as long as the inventor has never applied for a patent, you can apply for patent registration yourself, and applying for a patent has priority, that is, whoever applies first will have a patent right. Just remember to pay the annual fee after applying, otherwise the patent office will think that you give up patent protection on time, the patent is open, and others will not generate patent royalties.