Hi, I am trying to learn the beginnings of how to scrape data in a website using Javascript, and I am a babe in the woods unfortunately. I have a website with a field I am trying to read the result from (starting with XLV HALO...). How would I go about getting the results of this field either using KM directly, or Applescript, which would be executed through KM? Any help would be appreciated.
I'm no JS wiz, but I'll have a go while we're waiting for @ComplexPoint 
The general form for getting this sort of thing is
referenceToElement.attributeToGet
Luckily this button has an id -- id="select-chart-button" -- and ids are required to be unique on a page. That means we easily get a reference to the element we want without having mess with an array of objects
getElementById("select-chart-button")
You can see a list of a button's attributes at <button>: The Button element - HTML: HyperText Markup Language | MDN. From that and the "Accessibility" section of your screenshot, the name attribute looks like a good bet. Putting that together with the previous and we have
getElementById("select-chart-button").name
So I'd try that in an "Execute JavaScript in Front Browser" action and see what happens:
What kind of value / result do you need ?
More importantly, what is the problem that you want to solve ?