And which information was that?
You should be arriving at this: https://docs.python.org/2/library/functions.html#range
It's using lists, addition, multiplication, mentions for-loops, arguments, some math. Most of these should be familiar, and even if you don't understand every single thing, that doesn't mean that it can't still be understood as a whole by puzzling together the rest. So which of them would need to be worked around in a different explanation?
It may also be that you should spend a bit more time reading it, it is fairly plain.
There are multiple examples involving step, and it says what it does with the step argument.
It also mentions arithmetic progressions, there's a wikipedia article on that, reading the first sentence of that article should tell you all you need to know about what that is.
You've also got the ability to call the function yourself and play around with the arguments and make observations about the outcome.
You have so very much information here, lots of overlapping things, you don't need to understand all the information, several parts by themselves are enough.
Most likely, you should spend more time with the information you have. Or you should be pointed at which information exists.
I absolutely understand that it still may not be easy to understand, but "doesn't work, explain it better" makes it impossible to understand what you need and most likely you don't need anything more anyway. But if you do, you'll need to be incredibly specific about what you ask, take the drivers seat instead of making it somebody else's responsibility to guess what you need.