In Blender v2.82 I’ve run into an issue with the parenting shortcut CRTL + P. Didn’t seem to matter the order I selected the camera/empty or empty/camera it would always set the empty as a child of the camera. This hung me up for a few.
Instead, in the Outliner, I drag the camera over the empty – when dragging a tooltip pops up up indicating you can hold shift to set what you’ve dragged over to be the parent of what you are dragging. So, hold shift and drop the camera on the empty, and it’s now setup with a parent > child relationship.