If you want to automatically send emails through your SendGrid account when you update your Google Sheets spreadsheets, you can do that using Zapier.
You will need:
To link your Google Sheets to SendGrid, you must have an active SendGrid account. To learn more about getting started with SendGrid basics, start here. For more information about getting started with SendGrid on Zapier, go here.
Click here to Send SendGrid emails from new Google Sheets rows.
Now test the Zap to make sure it works. Once you’re satisfied with the results, newly updated rows in Google Sheets will send corresponding emails through your SendGrid account.
If you ever want to change this Google Sheets and SendGrid integration, just go to your Zapier dashboard and tweak anything you'd like.