First of all:
I don't want to sound harsh, but these are very basic things anyone, that has dubbing/mixing experience, should be able to understand if he or she steps into a studio.
1. Did you get a manual or can you look it up on google? You'll need the model number.
2.If you do dubbing and mixing, don't you know some people that can help you out?
Ok that did sound a bit harsh, let me give you some quick and dirty answers:
The polar pattern allows you to choose between several patterns, like:
Omni: most natural sounding, records everything around the microphone, not a typical VO setting because room acoustics will be picked up also.
Cardiod: More focused soundfield to where the mic is pointing (there's a front and back to a mic, figure that out first). Usefull for VO, first choice with a mic in a reflective room.
Figure 8: Special pattern, google it, can be used for VO, not first choice in my opinion.
Level/dB switch: allows you to attenuate the level from the capsule before it goes into the preamp. Prevents distortion with loud screaming. Not very useful for VO.
Sometimes there's a freq filter: useful to attenuate low frequencies, not especially necessary for a VO unless there's a lot of low end rumble from adjacent traffic or machinery that distorts the preamp.