Saving OneNote Note Books to SharePoint

Open OneNote and Click on Share > Create Shared Notebook...

Enter a Name for your OneNote Note Book and chose a template that’s appropriate to your needs and click on Next

Choose Multiple people will share the notebook and select On a server ... in the other options and Click Next

Click on Browse... button and select the destination path. You should save it to a document library in SharePoint. Check the checkbox shown at the bottom if you want to send an e-mail invitation to other people, click on Create

A Note Book will be created in your SharePoint site with which you can collaborate with other colleagues.