A Microsoft file hosting and synchronization service.
Hi Dan,
If you are talking about that you want to sync a library in a site collection library in SharePoint Online to the local computer with OneDrive for Business 2013/2016, you don’t need to copy the library URL you want to sync, you can refer to the steps in the following articles about how to use OneDrive for Business 2013/2016 and what is a library.
What is OneDrive for Business?
Sync files to your computer from a document library
After you knew the libraries, I suggest you use the OneDrive for Business Next Generation Sync Clientif you only want to sync the OneDrive for Business library.
Thanks,
Cliff