Web application to upload pdf files onto a Sharepoint site's library

Hello,

I am in charge of developping (with Djangp) a web application which will have to upload files ta a library of one of our Sharepoint sites (Office365). This web app will be hosted on Azure

Currently, all of our users have to login on the sites with login/password followed by sms confirmation.

I am looking for ressources explianing the process of having my web app authenticated to Sharepoint (getting a token) and then uploading files to a given library.

Thanks for your help