Hi @ross,
odrive will give you visibility into your existing Amazon Drive data, as it is currently structured. When you link Amazon Drive you will see it appear as a placeholder folder in the odrive folder on your desktop. From there you can navigate in through the structure, downloading only what you want to download.
Take a look at the video on this page for a walkthrough:
You can also take a look at our usage guide for basic information on using odrive to sync your data: