Hi Bruce,
Does the flash have a hot shoe?
If so, you can simply attach it to the D7000, but be aware that the camera won't 'know' you have a flash attached*, so you cannot rely on metering a scene.
If it doesn't have a Hot Shoe (I'm currently using one that doesn't), then you probably need a
Nikon AS-15 (since your D7000 may not have the necessary socket - my D7100 doesn't), which is a small device that mounts in the hot shoe and has a 'PC/X' socket on the front that probably suits the cable on the flash gun.
The same goes for shooting though*, you'll need to shoot in
Manual only; set shutter speed to 1/200s (or less), choose an aperture and ISO, take a shot and review the histogram and adjust aperture and/or ISO and/or flash power to achieve a correctly exposed shot. Have a play, you'll get used to what affects exposure, whether direct or bouncing off the ceiling.
I recently shot
these by this method - I'm quite pleased with them - but I'm going to buy a more modern, semi-automatic, flash - capable of remote (cable free) use 'off camera'. I'll be posting a thread here on my selection criteria for this soon.
Good luck, Dave
PS - you probably won't be able to use the camera in 'Commander mode', that requires a flash with compatible electronics (Nikon or some third party) and you have not said which flash make/model you have - please advise.