Parents who read to their children have children who can read
I agree that's a very good idea, but my parents never read to me (nor anyone else), and I was reading above average in the second grade.
Most of the students in my class were reading as well. That was close to sixty years ago. We learned the alphabet, started out with simple classbooks, and went from there. I clearly remember getting good at reading sentences and paragraphs early in my second grade class.
I don't think there's anything too complex about learning how to read. Not when you have nuns demanding that the students memorize the alphabet and other word-related lessons.