Here is my code and it works (I used NuGet package Select.HtmlToPdf. Document.Save saves the PDF instead I would like the PDF open for user to review (instead of saving in computer)
HtmlToPdf converter = new HtmlToPdf();
// create a new pdf document converting an url
PdfDocument doc = converter.ConvertUrl("www.cnn.com");
// save pdf document
doc.Save.(Response, false, "test.pdf"); // false: will not save the document
// close pdf document
doc.Close();