I love both fiction and nonfiction. I love reading historical fiction and love when a story has so many factual elements that I have to double check if it was a true story or not.

I would seek out fiction that is on the same topic as your favorite nonfiction books. If you like science there are scifi authors who use a lot of real science in their writing. If you like true crime there are a lot of authors who write very realistic crime fiction. Politics, history, etc all have fiction writers who know their stuff.

Edit: it’s also OK to just stick with what you like. Not everyone needs to like fiction.