Walnut trademark, does it mean that your main product is walnuts, and you want to apply for a trademark? If so, the category you are applying for is

Class 29 , processed walnuts, if you have other things you want to expand, you can apply together, such as processed drinks: walnut drinks, walnut-containing drinks, etc., which belong to category 32, and there are other related categories, but the main one is category 29 , if you have a good trademark, you can check it in advance, so that the registration pass rate will be higher