I don’t think that’s true, at least in the US. Patterns can be copyrighted, but since there are so many iterations of similar styles and patterns, it’s probably tough to enforce (not that I’ve ever tried.)

I knit and crochet, and sometimes pattern writers will try to forbid people from selling the items made with their patterns, which is nonsense. The pattern itself is copyrighted, but not the item made with the pattern. I always find it vaguely annoying, and hope people don’t buy into it.

Honor Raconteur sells her books on her website, I believe. https://www.raconteurhouse.com/

Mrs Bradshaw’s Handbook, by Terry Pratchett comes to mind, although I suspect you aren’t looking for a book about a train journey through an imaginary landscape.