I have a 1099B that shows a loss from a futures account in TradeStation....I am using the self-employed version of TurboTax....how do I enter a loss? I only see gain.

if you have a substitute 1099-B for futures, you need to enter it under 1256. TurboTax supplies two boxes. one labeled gain and one labeled loss.

Depending on your trading results, choose the appropriate box. Enter as a positive number.

Under Investment Income Start/Update  "Contracts and Straddles"
Continue twice and check the box for Section 1256 contracts marked to market.

Thank you!  And how do I handle the question regarding amount to be carried back?