I'd think less about "I want to start a startup" and more "I have a product idea that I think I can build, people will want and I can charge for it" and go from

I'd think less about "I want to start a startup" and more "I have a product idea that I think I can build, people will want and I can charge for it" and go from there. If you want to learn about startups, best is to go work for one.