How to move / exclude default objects?

I have two objects present in the default scenery that I’d like to move, as
shown below.

However, I can’t
find either 1) instructions on how to select or move a default object, or 2)
an exclusion setting that hides these. Bonus issue: As you can see, terrain
scenery is showing through, and polygons don’t appear even with zooming
around. Haven’t received help so far, and haven’t figured it out… [here’s
the post about
Any help appreciated.

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