From these examples, you don't have to do anything special in the early years besides talking and reading to them (and of course, building a home/family they can feel safe in -- all the stuff that normal parenting advice is about). In the next few years after that, you can add on some enrichment material depending on their interests. For example, Art of Problem Solving has this really nice "Beast Academy" series of workbooks that goes through elementary and middle school math, but with deeper questions. If they really take to a subject, you just keep feeding them more of it. It'll be fun for them, and neither expensive nor time-consuming for you.
At some point, their interests will become specific and deep enough that you can't lead them, at which point you should get them in contact with peers or mentors, e.g. through summer camps, competitions, or a magnet school. Once they're in that network, it's smooth sailing: they'll tell you what they want to learn! In other words, in general a parent with a full-time job cannot feasibly guide a talented kid's intellectual development up through age 18 (though of course your still are responsible for their moral development). Intellectually, your job is just to nurture their interests, give them the boost they need to get going, and then cheer for them as they continue on.