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!
If you have the 16 digit License Code you can download it from here,
How to get started with the Desktop program, install and activate it
https://ttlc.intuit.com/turbotax-support/en-us/help-article/product-delivery/download-software-turbotax-com/L7u9oLEkq_US_en_US?uid=luqgvzrd
Was your Amazon purchase "Shipped and Sold by Amazon or Amazon.com"? If not, it might not be authentic TurboTax software. See Where can I purchase authentic TurboTax Desktop software?