I am working in SharePoint Online with Office 365.
I need to create a REST API so that an external program is able to access data that I will have in a simple document library. It will have folders that goes only one level deep.
Also, our SharePoint online requires a username and password to access the main level site.
How do I ensure this works? What do I need on my end or on theirs?
I am really new to this. Please guide me how to achieve this?
Thank you for your help.