shutter speed of D700 camera?

What is the shutter speed of D700 camera? Can the existing shutter speed increase? If yes, how?

please read the manual regarding this. Of course the shutter speed is variable as it is in any SLR.

These types of questions always make me curious as to why you would ask. Can you share the "why" behind the question?
If you are talking basics, then you have to change the setting to "shutter priority" and adjust using the control dials. If you're
asking to increase/decrease the pre-set camera parameters, then I don't have a clue as to how to do this, nor do I understand why. I
am curious!

if what you mean is the flash synch speed, then yes you can increase it in the custom funtions