Hands down... Khan Academy.
Most of the stuff you list isn't really economics topics; you might find the sort of stuff you're looking for in legal texts instead. Something like a corporate finance book or class would be a good starting point. (Business schools also cover this stuff, but it's likely to be dumbed down compared to law school versions.)
The basic law school class or casebook (a casebook is the law school version of a textbook) is generally titled simply "corporations" or "business organizations" or something like that.
I have taken a basic economics course and read some academic economic stuff here and there, but these have been viscerally “theoretical” in nature. I want to understand real-world concepts like value chains, stocks, venture capital, IPO, corporations (I can’t quite say I know what a corporation IS.) ... . The best resource I have found to date is http://stratechery.com . I am wondering if more efficient learning material exists. I don’t want advice/prediction books (on management or investing). I simply want to understand the basic stuff about these concepts. Financial literacy, I would say. I don’t know if there is a name for this ”field of study.”