Before I start, let's get something out of the way:
So long as they have the appropriate privilege, a user can downvote a post for whatever reason.1
Though you haven't explicitly stated all of them, I am going to address a few of what I presume are your concerns:2
What is Super User supposed to be about?
I asked if something was possible and my question got downvoted for kingdom come. Isnt this what this site is supposed to be about?
This site is about computer software, hardware, and home networking. Asking if something is possible can potentially be on topic. Autoruns and viruses are within the scope of the site.
Generally speaking, the site and other StackExchange network of sites aim to be a repository of high-quality question and answers for the benefit of future users.
Why was your question downvoted?
Isnt it crazy to downvote a question just because the asker doesnt know something and wants to learn something about it?
To be blunt, I don't believe your question was downvoted solely because you didn't know something and wanted to learn about it.
The tooltip for the downvote button says:
This question does not show any research effort; it is unclear or not useful
Your question as it is at the moment, with the vote breakdown expanded:
"Put Read Only autorun.inf and a autorun.bat in the root of the USB to keep musallat.exe and özel dosyalar.exe away" - the question does not explain what 'mullasat.exe' and 'özel dosyalar.exe' are in sufficient detail. You recognise this might be an issue by starting to explain this in a comment, but then talk about another thing, helalet.exe. Information pertinent to the question should be in a the question, not a comment.
"They just make folders hidden and put folder shortcut.exe's" does not explain what they do enough for someone unfamiliar with them to know what effect they would have.
"Will my plan prevent all kinds of USB viruses?" - this is answerable in the narrow sense, but broad in the the wider sense
"Are there other viruses that will require antivirus on PC?" this also answerable in the narrow sense, but broad in the wider sense
It is quite possible for someone to answer your question along the lines of "1. No 2. Yes". However, the resulting QA would not be a useful resource to others.
So, how can you improve your question[s]?
Start off by reading How do I ask a good question? or re-reading it. It has useful pointers that would have helped you avoid attracting downvotes, in particular:
- Search, and research
- Be specific
- Make it relevant to others
Good luck, I hope you are able to edit your question and improve it.
1: So long as it doesn't form part of a bigger pattern of vote fraud or serial voting
2: I have answered your presumed questions as I would like my answer to be useful to others as well as you. I don't believe it was your actual intent to ask if the site's users are literally crazy, as that would hardly engender goodwill.