I have capital gains that are already included in my wages on my w2, why do tthey get added to my income a 2nd time?

[MichaelDC]

1. The profit from the sale of your stock options has been reported on your W-2.
2. In addition to that, you may have received a 1099-B reporting the sale.

You clearly didn't receive a profit of the total amount reported in the Proceeds Box 1d 1099-B. 

The basis (cost of your investment) is seemingly "0".

If that were the case, "yes" you would be taxed twice.

To correct this situation, you report the basis (in box 1e and on TurboTax) to be the compensation amount that was added to your W-2. Most of the time this is a "cashless transaction" and no additional shares were sold that weren't already accounted for in your W-2. (See Screenshots below. Click to Enlarge.)

Only, if the 1099-B reports an incorrect basis:

1. Enter the 1099 as is then 
   
2. Click  Add More Details or Edit
   
3. Select the option  "I'll enter additional info on my own" (or just click Continue if the "on my own" button isn't present)
4. Scroll to "Corrected cost basis"
   
5. Enter the correct basis (in most cases the same as your "Proceeds")
6. Click Done
   

TurboTax will report the sale on Form 8949 "as reported by the broker" but will put an adjustment figure into column (g) of the Form, a code "B" into column (f) of the Form, and the correct amount of gain or loss which includes the adjustment.