replicating a form field which is connected to onedrive

Hi folks, I am building a new website for my client and I am looking at replicating a form field which is connected to one drive. Basically, the way this works is when a new client is onboarded the company creates a folder on OneDrive and gives access to the client's email. Upon email verification, the client can log in to the OneDrive folder by simply inputting his email in the form field (happy to provide link). I've been breaking my head on understanding what is used at the backend for months. I have received the panel access but have not been able to figure out anything. Any help will be greatly appreciated.