Nobody can put one's own brain in your head. If you don't understand something in the API, which is quite well documented and simple enough, it means you need to take a step back and learn the basics: working mechanisms of variables, fields, methods, properties, method parameters and so on, how the language and platform work together.
If you don't know where to start, showing the starting point cannot help you, as next time you won't be able to see where to start again. Perhaps, a recipe for you would be: 1) never do the job in which you don't know where to start, make a step back, 2) make sure your are not standing at the same point, do the progress.
Sorry, this is pretty much talking about nothing, but I feel you would need something like that.
As to the saving of the screenshot, this is explained here:
http://pcsxcetrasupport3.wordpress.com/2012/03/09/windows-form-screenshot-and-print-preview-in-vb-net/[
^].
However, it can be the problem again. You can learn how to make a screenshot, but it won't help you to solve your next problem. Will it help you to know where to start? You really need to develop a development method, and the method of reading and understanding documentation, and the method for the search for the documentation. The method of thinking. How to get there? By starting with problems which are easier for you. This is trivial, but the truth is often trivial, after you know it.
Good luck,
—SA