This can be done a variety of ways:
The simplest is to use links to separate pages per o/s and language. They can be styled to look like one page. Or...
You can use links to load the respective o/s and language sub-pages into an Iframe. This avoids duplicating the page structure and menus etc. on multiple pages.
You can go the whole hog and use PHP and SQL to set up and use a database of info.
My advice would be to start simple, and incorporate more advanced features as your knowledge grows.