Google Sheets App Script Not Showing Up at the Top (here's why and a fix)
My 'real' job is building financial model templates, check them out: https://www.smarthelping.com/p/excel....
I ran into this issue working with a few clients and the only fix is you have to open up a new blank Google Sheet and then the Extensions tab at the top will be visible and you can navigate to the App Script section.
If you upload an Excel spreadsheet directly to Google Drive, the Extensions tab at the top won't be visible and there is no way to add it in from what I can see.