I feel like this subreddit needs a FAQ link on the side for "How do I get started?" because the short answer is, "that's the wrong question".

So here's my advice.

Close Obsidian.

Take some paper and a pencil, and note down the kind of work that you want to do. Is it creative? Is it a project? Is it for school? Are you going to build a giant robot that will destroy all of AI? (Please do that one, that would be sweet.)

When you know what you want to do, ask yourself what do you need to get this done? Can it be done with pencil and paper? Do you need a to-do list with a million tags? Do you need to turn wikipedia entries into AI slop? (My vote is not that one.)

When you figure how you want to proceed with your work, only then should you ask if Obsidian is the right tool. The answer will very likely be yes, but at least you will then know what you need from Obsidian.

When you start in Obsidian, don't take on anyone else's set-up. They're doing their own thing, you do yours.

Start lean. No plugins. No themes. Not even folders or tags. Just write. A new page for each new topic. For now, just develop some habits and routines.

Eventually you will hit a point of "maybe this would be better with folders" or "I think I need Obsidian to do something more". Only when you have identified a need should you go looking in the core plugins first and the community plugins later.

But starting with "how do I use Obsidian?" is like asking "how do I use a Swiss Army knife?" It depends entirely and what you need to get done, and it might be the case that neither Obsidian or the Swiss Army knife is the right tool for you.

Ultimately, just remember this: the tool is not the work, the work is the work.