when you create a new level, it comes with a floor but not a landscape (if i am not mistaken)
what is the difference between a floor (As static mesh) and a landscape other than you can sculpt and paint a landscape
if you have a landscape, do you still need a floor?
You can delete the mesh.
Maps don’t come with landscapes because it’s not the standard. That mesh is just a test ground. If you want to create a map to work on code, it already includes that mesh and lighting to save you those steps.
I usually start by creating an “Empty Map.”