it is important to learn perspective but i dont know that point perspective is needed here.
hard to say since most of us aren't mind readers and i dont think OP explained very well but i imagined this as some sort of scrolling map, in which case a consistent overhead angle would suit.
something like this:
another thing REALLY bothering me is the far too obvious vertical line of symmetry formed by the waterfalls.
it looks silly and unnatural, as well as doing no favors to your forms (doesn't help sculpt/describe your shapes).
you should look for ways to vary things so they still balance but look more natural.
here's a quick example:
as mentioned, don't take these edits too literally and just copy what is done as our edits are not THE way to draw it.
rather try to learn/ask WHY and HOW we come to these conclusions.
i also don't like the cylinders of your center island.
i think they are too regular, square-edged/geometrical, symmetrical, chunky, and boring.
you should try starting by sketching a bunch of overlaying cylinders that of different diameter and heights, then rough them up into more natural shapes, smooth some edges, keep some sharp cliffs etc.
