For books only available through Amazon my workflow used to be buying it, downloading it with their desktop app, importing into Calibre, converting to epub and stripping DRM, then pushing it onto my Kobo. They broke that a while ago by making their DRM even worse, so now I just pirate those books.
Books have got to be the least expensive form of entertainment out there. The value to cost ratio is incredible. Consider buying books to support authors and publishers. If you can't afford it, then libraries are nice too. I personally know people who pirate books, but pay hundreds of dollars a year for streaming services or battle pass type video games. It blows my mind. Books are so cheap people! I recently bought…
I've been downloading every book whose title I see mentioned anywhere. I've got the last 20 years or so of the NYT Book Review Notable Books (100 per calendar year), the Book of the Month Club list, etc. Why go to the library, when I can have one of my own?