I need to enter a sale for coinbase. Most info is auto input but I need to input the amount of Proceeds and Cost or other basis. My CSV says it is $0. Should I put $0?

Your basis probably isn't zero.

Cost basis = Purchase price (or price acquired) + Purchase fees.

To Adjust cost basis

TurboTax has made allowances to make this correction. 

1. When posing in the Stock area there is a check box Under Box 1e -

   1. Cost or other basis 

   2. Report the basis as it shows on the brokerage firm

2. Below that you will see 

   1. The cost basis is incorrect or missing on my 1099‑B

   2. Check this box and .. Continue

3. Let us know if any of these situations apply to this sale

   1. None of these apply .. Continue

4. We noticed there's an issue with your cost basis...Let us know if you'd like to make any changes

   1. I know my cost basis and need to make an adjustment

   2. Enter the adjusted amount