The code is too big (> 5k lines). F5 is exactly what I did and then the above error information appeared. I believe it was a stack overflow and since the code is big I need to locate.
Learning how to debug with VS (or any compiler/IDE) is not something easily explained in a single, short 8,000+ character post. All I can do is point you to a resource to learn on you own, at your pace:
Introduction to Debugging
https://blogs.msdn.microsoft.com/visualstudio/2015/08/11/introduction-to-debugging/