From any browser on any device, easily sign in to OneNote Online so you always have access to your notes.
Sign in to Office.com with your Microsoft account, or work or school account.
Select OneNote.
Select the notebook that you want to open.
Work in your notebook just like you do in the OneNote app on your desktop or mobile device. In OneNote Online, you can:
Add sections or pages
Add notes and format them
Insert pictures, tables, or links
Draw or handwrite notes
Share your notes with others
Source: Microsoft