I want to show you how to read a private Google Sheet into Deepnote. There are a few steps that are not obvious at first but this guide will help to clear things up.
At a high level, we have to create an "identity" with Google, share our Google Sheet with it, and then assume that "identity" in the notebook.
Speaking of the notebook, here it is. All that is needed is for you to duplicate it into your own workspace and paste in a few values associated with your Google account and Google Sheet.
Check out this video walkthrough to get up and running.