@rnbramirez asked: "if i bought tt online where do i enter product key code?"
Are you asking how to download and install your desktop software that you purchased online, and how to enter the license key? If so, see the steps in this FAQ which includes a screen shot:
FAQ: How do I get started with TurboTax Desktop?
https://ttlc.intuit.com/turbotax-support/en-us/help-article/license-information/install-turbotax-cd-download-software-license-code/L1wFOSXur_US_en_US
Or did you purchase desktop software and happened to use Online TurboTax (web browser version) by mistake instead? If so, the license code for desktop TurboTax cannot be used in Online TurboTax. If that's your situation, we can tell you how to switch to the desktop software you purchased without starting over.