Vikas,I remember in my D5100 there was option when I used to get 3 shots by pressing shutter button once.
And what I knew that if we are shooting moving object then Keep focus AF C and if still then AF S.
How many shots will I get by selecting CH? I have been using D7000.
No. of shots depends on the camera buffer and the speed of SD card.. Unfortunately, D7000 has low buffer.
Maybe you can still get 3-4 RAW shots and maybe 15-20 JPG. Look for this info in your manuals or web. I don't own this camera, though I had borrowed it from my brother to shoot video quite some time back.
Its a nice camera.