Ok.... My Cat Gave Birth To 6 Kittens 2 Weeks Ago. So Now When Should I Give Them A Normal Bath?

The mother cat should be licking them clean by herself. You should avoid getting kittens wet when they are that young. They cannot regulate their body temperature when they are that young and you may actually cause harm if you bathe them this soon.
  If it is an emergency like if the mother cat has fleas, then the fleas could literaly suck the kittens dry of their blood. Call a veterinarian and ask them about what kind of flea control you can put on the mother cat.
  Be aware that your mother cat can get pregnant again even before she weens her kittens so keep all the boy cats away from her until you can get her spayed.

She will clean them, if you must clean them you need to wait until after 6 weeks.

I was just informed today to wait until 8 weeks old.  Mom should be doing a good job of it but if you still want more it is fine to use plain blue Dawn dish soap, as early as 4 weeks.