Austin,
The lake in the background of your shot is like a mirror; during the day it reflects the sky and clouds above. At night it reflects the darkness. It cannot be lit per se. The best you can do is put a light on the opposite bank from where you’ll be shooting and create sparckly highlights on the rippling water (best to place the light high enough to be out of the shot).
Another alternative is shoot at magic hour, when there is still enough ambiance to see the background. This presumes you have control of when the interview will be done and that it will last only a short period of time. If neither of these are true, you best wait until it’s full night and maybe twist the background to see the edge of the lake where it meets the shore and a bit of water. These are objects that you might be able to light with you minimal kit.
JS