I see. So you have something like I show on the left but want what I show on the right?
There was a change to the way the camera works in SU2020, although I forget which revision, that in simple terms lets you get the Parallel Projection camera in closer to the model so foreground content is behind the camera. There are several ways to do this. For the view on the right I started with the camera set to Perspective and set up the view so the trees are behind the camera. Then I switched to Parallel Projection and created the scene.