Add OneNote in Sharepoint Site Grp
Go to the Microsoft Teams
Click on Teams icon that is on the left.
Select the GRP-IT Happenings Group, follow the below Steps to add OneNote.
In the dropdown Menu select Documentation
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Click on Files and Select your team folder.
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Once you are in your team folder.
Click on the dropdown list and select OneNote Notebook to add.
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It will be added to your Team folder.