By default, Inform doesn’t have any graphical capabilities at all – it’s a pure-text engine for programs that take text input and produce text output. The default text-orientation of Inform is intended to produce programs that can be run in interpreters on many many kinds of devices, some of which have no graphics capabilities whatsoever.
Inform can be extended (using a variety of extensions that are not part of the core language) to produce programs that allow for more graphics-inclusive output and graphical input, but this is not a simple or easy thing to do. You can use Vorple directly with Inform: that’s what it was specifically invented for! But doing this is not the kind of thing that can be easily explained in a single forum post (and I am in any case the wrong person to write such a tutorial, as I have only played briefly with Vorple). Vorple’s website has much more information than could fit in a forum post, but knowing at least the basics of Inform is probably necessary to start understanding the documentation.
Again, there are other ways to get graphics-based input/output with Inform, and looking through the available Inform extensions is one way to get a feel for what is possible. Here is a forum thread on where to find Inform extensions.
It may be that Inform is not the best tool to accomplish whatever your overall goal is; you’re not very specific about that goal, so it’s hard to say. One red flag is that you ask how to “change the position of an element on the page,” which is something that doesn’t map onto Inform’s default model of text processing, which does not produce a “page” at all, but merely a text stream. (Again, extensions like Vorple can push this model in a lot of different directions, but the default model of Inform doesn’t have a concept of what you’re asking to do when you use that phrase.) Depending on how you envision your game working, it may be that you should look at Twine or Ink, if you’re not trying to do something parser-based, or else at Adventuron, if you are.