Just to clarify (it has been mentioned), you really should have two cable release cables;
- You need one to do mirror lockup shooting
BUT
- You will need two if you are using mirror lockup AND bulb-shooting. (press and hold the camera attached one to lift the mirror, then press the lens attached one to open the lens aperture, release the camera attached one to close everything and bring the mirror down again).

I have a 50mm and a 110mm lens for mine, I am on the look-out for a 150mm or a 180mm lens for it.
(divide by around 2 to get the 35mm equivalent focal length when you are shooting with a 6*7 back).

As mentioned, check the manual carefully to get a good idea on how the camera works, you can also check out youtube to see people loading the back with film if you are unsure how to do it.

It's a big bugger, so I've been using it on tripod only so far, but when the light is good and the shutter speed is fast enough, it should be doable to shoot hand held. I would believe that it is "even easier" with a eye level viewfinder and the winder.