It actually a lot more simple than it looks and you need RAR to extract most files. You can find that on the play store and it looks like a bunch of books.
If I remember correctly you have to extract the file, Click on the HTML and hit whatever browser you mainly use. It didn't work as well for me on internet but it worked better on chrome. But if it works better like that for you then that is ace. Also there is a chance that images might not work but that is slim.