If you made a list of all the things you really do know, you would be amazed at how long the list is. The longer you've been living, the longer the list gets. It might not be about using computers. It might be about wine making, or appliance repair, or air traffic control. There are Q&A sites about all those things.

How did anybody learn about netsh? The person who wrote it knew about it. If that person told 10 people, and each of them told 10 people, it wouldn't take long before a billion people would know about it. Can you figure out how many iterations it would take? See, there's something else you know!

I know more about designing and building relational databases than I do about Windows commands (actually DOS commands). I get a little bit of rep over in SO out of that. I don't have much rep here. But rep isn't the main reason I answer questions. It's trying add a little bit that's needed by somebody, somewhere. Of course, most of what I learned about computers is too obsolete to be of interest here in SU. But if they ever start up an area for computer topics from the 1960s and 1970s, I expect I could answer some questions that few other people could.

The more interesting question you raise is how do you get to the point where you can independently solve problems on a computer? One way is to learn how to use tools like Word, Excel, Access, Photoshop Dreamweaver, and the like (or competing products). Another way is to learn how to program (assuming you don't already know how). I can't tell you how to learn programming today. It's too diferent from how it was when I started. But I'm sure other responders can.

I will tell you that, to a non programmer, a computer is like a stereo system. First you buy the stereo, then you buy the music. To a programmer, it's more like a piano. You buy the piano, then you make your own music. If you're Mozart, you don't even have to get somebody else's sheet music. You write your own!

I don't know if any of this really responds to what you wanted to know. But I guess I'll find out!

Netsh is a tool. How do you first learn about any tool? You typically learn from somebody that knows how the tool works and, more importantly, knows what the tool is useful for.

Over the last ten years, search engines like Google and Q&A forums like Superuser have facilitated encounters between people who need the knowledge and people who have the knowledge. You've already commented on this.

Back in the stone age (which always ended about ten years ago), there was face-to-face Q&A, presentations and lectures, and tutorial documentation. There are probably some excellent tutorials out there that introduce the Windows user to networks, and many of them probably bring netsh into the discussion. These vehicles reached a comparatively limited audience.

Here's the good news: over the course of your life time, you can expect to add considerably to the array of tools and techniques you can draw on in any given situation that calls for diagnosis and repair.

Here's the bad news: Over time, you can expect much of your knowledge base to become obsolete.

Here's more bad news: while you are expanding your knowledge base, the total knowledge base is expanding at a much, much faster clip.

So, over time, you can expect to become absolutely more knowledgeable, but relatively more ignorant.

Welcome to the club!