Even if you only want to write science fiction, you should also read mysteries, poetry, mainstream literature, history, biography, philosophy, and science. ↗
I've loved science fiction ever since I was a little kid, mainly from looking at the covers of science-fiction magazines and books, and I've read quite extensively as an adult. ↗
I cannot say how strongly I object to people using other people's writing as research. Research is non-fiction, especially for horror, fantasy, science fiction. Do not take your research from other people's fiction. Just don't. ↗
It's kind of a misnomer about science fiction that science fiction is about anything other than people. It's about people doing stuff, sometimes doing extraordinary stuff. ↗