I do not know where to start

I have used windows all my life and I really want to start learning linux and i do not know where to start. I applied to a course on coursera and all they talk about is that it's open source and the history of linux etc. There are millions of books out there and i dont know which one to choose. I am even scared to ask the wrong questions. I dont know which distro to use and i do not know where to start. If anybody started out like me could you please give me some tips?