How can I send a response e-mail containing a value from a Google?
If you wanted to send an email using the next promo code in Excel, Id suggest that you use the Mail Merge feature in Microsoft Word. You build the text template in Word, then use its Mail Merge wizard to grab the data from an Excel workbook, sending emails populated by successive records in a table. This is a pretty easy task, and is frequently handed off to departmental secretaries or administrative assistants. Google Docs has a similar feature. It also appears that you can drive a mail merge direct from Google Sheets. In the linked webpage, the emails will be sent by gmail.