C++ is different from this. This is C Sharp, which is based on the .Net framework, while C++ is not. Purely for Web Design you can use C Sharp and use it with ASP for Web Functionality. I've also heard people touting Python and Ruby as excellent Web Design Scripting Languages, but I have not worked with them in more than a cursory form.

If you know HTML, learn CSS next. It's the foundation that will tie your HTML together and make it easier to use.