control-P on windows or command-P on osx to open the print menu. Then pick the pdf printer or (on mac) the pdf dropdown. This will "print" to a PDF file. If you are using windows and don't have this stuff, then you need software. Downloading software sounds overly complicated for me to explain in this circumstance. There are forums on different websites that you can use to learn how to use your computer if you really want. Otherwise, for now, just save the webpage as a web archive from the File menu in your browser.
