The final step is to create a Web page from your data. All you need to do is click on "Export/Import" from the File menu, choose Make HTML Page then give your page a filename. Use the filename "test.htm".
The program will tell you that it has produced a file, and let you view it in your browser. (Note that the single-file output is an improvement over previous versions of Hot Potatoes, when three or more files would be produced for each exercise.) All you have to do now is upload that file to your Website, and you have a working exercise.