Hello @JamesRong
Thank you for contacting the Instructure Community. Yes you can integrate Onenote to your course and use them within assignments. First, you will need it installed and integrated in the course - is it already there? Do you see it on your navigation tabs on the left? If not, you may need to speak with your school about getting it installed or you can try installing it yourself at the course level following this guide:
How do I configure an external app for a course us... - Instructure Community
Beyond that, Onenote should have more information for you on how to use it on our platform. There is more information here:
https://www.onenote.com/lti
If you still need assistance using it in your course, please reach out to your school directly who can assist with the setup.