Thanks guys for the responses.
I'd love to find where in the documentation it lists this kind of stuff. If I had managed to find it in the documentation I wouldn't be asking the questions. Everything seems to be geared at running through transformations and the documentation I've come across hasn't answered my queries.
For example: https://docs.kentico.com/k10/developing-websites/loading-and-displaying-data-on-websites nothing in there deals with the current document/page?