Hmm, I would actually suggest starting with The Last Wish, even though it's the short story collection, because it does set up everything else. Plus the stories are a lot of fun! On the other hand, if you've seen the show, you can probably skip it and Sword of Destiny, because the show borrows from both of those short story collections, and start at Blood of Elves. This is a pretty good discussion of which ones to read in which order: https://www.pcgamer.com/the-witcher-books/

Hope that helps! I definitely think more people should read the books - I enjoyed them a lot.