When debugging or building, I am receiving a "no sub main" error.........

Question

Can someone please tell me what this error means and how I can fix it? To me it sounds like, vb.net wants the code that I have to be inside of some main code like how c++ does. My teacher looked at my code & she thinks it is correct; it is just for a simple form. If someone needs to see the code I can put it on here when I get access to it. Thanks, Joe