Why am I so shy (Read all, please)?

I am the same, well was, but I'm 15. I started talking to many people by just simply asking stuff about school. Like: "Do you know how to do this one?" Or if you see that they are talking about something that you like, you can tell them you like that 2. And talk about it. If the person looks bored just change the subject. Im not really a good advisor but you can try that?