Been awhile since I played the first dungeon keeper and I wanted to know if there is a way to change the camera view to overhead, like you can with DK2 by pressing F5?

press escape in game, got to options menu
one of the options allows exactly that view, another controls gamma, another toggles wall height

There's no keyboard hotkey toggle for different wall heights/views in DK1 that I remember, but you can zoom in and out via the Home or End keys. Some guides say you have to Ctrl+Home but I never had to press Ctrl. Rotating the camera was Page Up/Page Down. I don't have the GoG version however, so if it's not working for you, and you're getting odd unprompted glitches, there could be some other technical issue you're having with the game/installer.

DK2 ... I can't even remember the hotkeys for that one.

what I usually do is hold down home till I am zoomed out all the way, and then click on the map and come out again, this automatically makes your view point north.

Ctrl+up/down did it for me

If you are on a macbook like myself you can rotate the camera / zoom by holding down fn and using the arrows keys