I bought the Turbo Tax CD at Costco because it is $30 versus $55. I already completely filled out my return online at the Turbotax website. Do I have to redo it entirely

I didn't have to and I did the same as you.  What you need to do is below.  It worked for me!

1. Save your online return as a tax data file.
2. Sign out of TurboTax Online.
3. Install your 2016 TurboTax software.
   • If you have not purchased TurboTax Desktop software, click here to select the product you need to complete your return.
   • Important: If your return includes a state, make sure you also install the corresponding state program(s), otherwise you'll get Error 539.
4. Once installed, choose File > Open Tax Return in the software program.
5. Browse to where you saved your .tax2016 file and click Open.