It does kind of depend on what sort of SF you're looking for. It covers a wide range, from hard SF where the scientist author provides technical details on how to build the interstellar craft in the book at the end through space opera to Star Wars style science fantasy, plus technohorror ones like Alien.
Classic Golden Age authors include Isaac Asimov, Robert A Heinlein, Arthur C Clarke, E.E. "Doc" Smith and Larry Niven. There is a definite dearth of strong female characters in the older novels (thank you Ripley!) but sometimes there are somewhat hidden ones. For harder modern SF, Andy Weir's The Martian is a good one.
I go back and forth on whether I prefer hard SF or space opera. I've recently been leaning towards more grounded stories, but that changes all the time.
I have read all three of Andy Weir's novels and really enjoyed them; I especially enjoyed how much of
Project Hail Mary was actually about linguistics, which is more familiar to me than the natural sciences. I also really loved
2001: A Space Odyssey (the movie) and have been considering reading the novel, which I know is by Arthur C. Clarke.
Solaris (1972) is another one I really enjoyed that's based on a book I haven't yet read. It's very psychological and about how humans think more so than the science. And my favorite science fiction story of all time is not a book nor a movie but rather an audio drama,
Wolf 359, which is also more introspective and about what makes a person, a person.
I tend to like SF and fantasy as vehicles for exploring very personal concepts, not necessarily as worldbuilding in and of itself (although I do appreciate well constructed worldbuilding). That's what I like most about
BtVS (and why season seven is kind of exhausting, once it becomes clear that none of the writers actually have any kind of idea for what this villain means on a metaphorical level)--while I wish that magic was perhaps a bit more
consistent, the mechanics of it aren't really the point. It's a story about adolescence more than it is a story about magic and monsters.