do i need to give vitamin 3 if i am giving omega 3 fish oil?

soory misprint on my part meant vitamin  E

Yes you do.  Depending on the size of your dog between 200 and 400 ie per day; look for capsules which actually say that it is d-alpha-tocopherol which denotes it is natural Vitamin E as opposed to dl-alpha-tocopherol which is synthetic; the former is more expensive but twice as potent and effective.

HTH