It should be in the email. Where to find the License Code
https://ttlc.intuit.com/community/tax-topics/help/i-can-t-find-my-license-code/01/852973
Amazon how to download and install your software order
https://www.amazon.com/gp/help/customer/display.html?nodeId=G2CJPY7HHXBLMR5E
To get the License Code from Amazon, One user said......
I was just having this same issue, but I just figured it out. So I thought I'd share in case you are still looking for an answer. Go to Your Account; then Digital Games and Software (under Digital Content and Devices section at the bottom middle); your TurboTax purchase should show there under Downloads and Codes; the license code will be the 16 digit code next to "Activation Key". Hope this helps!