So I am starting out on YouTube and wondering about copyright. If I post a video on YouTube about fixing Windows 10 or Something to do with that, can that be copyrighted?
When you produce a creative work and fix it in a tangible medium, which you do if you make a video and post it to YouTube, it is automatically protected by copyright. There is nothing special you need to do to copyright it. Note that by posting it to YouTube, you are granting YouTube a very broad license to copy and distribute the video.