Sci-fi book recommendations?

Ok, I have a confession. I’ve never read any sort of science fiction or fantasy book other than something like “1984“. I came across Dune in the bookstore the other day, and it sparked my curiosity. I’ve seen it compared to some of the better novels of the 20th century, including Lord of the Rings. Has anyone read it? Thoughts?

Similarly, if I were to start off with one book from the genre, what would you recommend? I don’t mind a bit of crossover with another genre, but think it’s high time I open myself to something new.