The following example shows you how to list files in a OneDrive folder.
To access OneDrive for Business with the API you have to set site url as https://<domain>-my.sharepoint.com/personal/<username>
If our Office 365 domain is "independentsoft" and username is "info@independentsoft.onmicrosoft.com" than OneDrive site url will be:
https://independentsoft-my.sharepoint.com/personal/info_independentsoft_onmicrosoft_com
*You have to replace "@" and "." from your username with "_"