The TurboTax online editions and the TurboTax desktop CD/Download editions are separate programs with a different price structure.
You cannot use the license code from one of the desktop editions on the online edition. Nor can the cost of the desktop edition be applied to the online edition.
You would need to return the software you purchased to the retailer for a refund if you only want to use the TurboTax online editions.
Prices for the online editions are here - https://turbotax.intuit.com/personal-taxes/compare/online/
