TL;DR

Use Google Takeout to create a zip file with all data you wish to keep from your Google Account (eg. Drive, Gmail, Chrome Bookmarks)
Back up the files you stored on your Macbook to an external drive or your personal cloud storage
Export data from apps (eg. Notability, Goodnotes, Canva) to a private (cloud storage) account
Log out of your Apple ID
Return the Macbook, charger and any other borrowed items) to the IT department

Account closure timeline

Service	Closure
Gmail	Last day of school (Except for Y13: October 31)
Google Drive	Last day of school (Except for Y13: October 31)
Veracross	Last day of school
Managebac	Last day of school
Seesaw	Last day of school

<aside> ⚠️ NEVER delete/remove/unshare any shared files/folders.

</aside>

<aside> 💡 Don't move anything out of a folder that other students at NIST need after you leave

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Move important files that other students may use in the following years, like documentation for service groups to the shared folder/drive of the group
For important files that are not in shared folders, please change the owner to the new person who will be responsible for editing the file.

Forward any important emails to a personal email account, that you may need to keep.
If you used your NIST email address to register on any website, update the email address on these websites to a personal email address.

Google Takeout allows you to download all data associated with your Google account. Depending on the service, the data will be in a different format.

For example: