How can I make an educational topic? (e.g. when I have made a successful finished project and I want to share it with the others) Is there any feature to do that?
By the sound of your question, I don't think this site is the correct place for you to make such posts, unfortunately. What you're looking for is a blog site.
EE.SE is a Questions & Answers site, so you'd have to carefully phrase a on-topic question to which your project is a valid answer. But even then, our site is more oriented towards receiving specific questions to solve specific problems. We don't usually provide full solutions nor design full products and circuits in respose to broad questions.
The site does allow users to ask and answer their own questions in one go, but these are usually tricky. These work well for frequently asked questions that we could point new users to. Questions that look self-promotional are not well received here.
Maybe you could post more details of your project so we can evaluate whether a question can be phrased to be on-topic here.
In any case, it's great that you posted this question here on Meta before posting it to the main site.
To add to @Ricardo's excellent answer:
When I come across puzzles or challenges during a project, and solve them myself, I sometimes look to see if there are any useful answers here about said problem. Occasionally I find the information I needed online, but it's spread out and often not easy to find. When that happens, I consider posting a question here and answering it myself.
You have to present the question from the viewpoint of someone having that particular problem, and think wording it in such a way that others can benefit from it. For example, did you learn new vocabulary words while you solved the problem? If so, the question should include the terms you used before you learned the proper ones.
Your answer can provide an explanation of how you resolved the problem, and correct misunderstandings or incorrect term usage. Again, the goal is to provide useful content for future visitors (not to mention yourself, should you come back to refer to it, as I have occasionally).
Here are a couple of examples of questions I answered myself:
- How do I create "beveled" T-intersection traces in Eagle CAD?
- Why would the VCC/GND pins of an ATtiny26 not be aligned?
Other times, I asked a question I already knew the answer to, but it didn't exist on the site, or wasn't presented in the same way I would have asked if I had needed to. In that case, I asked and just let other users answer:
There are also good opportunities to create question-and-answer pairs that explain a common misunderstanding. Consider Olin's legendary question-and-answer about choosing power supplies. I created one to help users with schematics, wiring and block diagrams.
So while these aren't tutorials or a blog sharing the details of your adventures, you can still provide some great educational resources.