Hello, I have heard about the ViewProjection class and kind of gotten an idea of it.

I wanted to know if it is possible to get an X and Y coordinate from that, if it is, then how would it be done?

What I am trying to achieve is drawing a 2D square pointing at an X Y Z coordinate. To be specific in what I am creating, I want to make a spinning hollow rectangle that points to where a waypoint is. I have already figured out how to draw the rectangle, now I need to figure out how to actually draw it to the position of where it is in the 3d world in a 2d form if that makes sense.

There is no ViewProjection class within 1.16.5. If you're asking about how to draw 2d objects in 3d space, look at how name tags are rendered on an Entity (can be found in EntityRenderer).