Document Generator from Google Doc Template

I don’t know scripting, but most people go low-code with this by using something like Make.com or On2Air: Actions. You could also use DocuMint, which has its own document template editor.

Hey Chloe,

You can create headers, footers, and add other elements to single or multiple templates by using On2Air Google Documents.

Here’s an example:
Create Automated Invoices in Google Docs and Airtable (+Free Template)

And here’s a comparison of On2Air Google Docs vs. Airtable Google Docs automation

On2Air Google Docs vs Airtable Google Docs

I've been down the Google Docs automation road before, and I totally get your need for specific headers and footers. While Google Docs automation doesn't have a direct template selection feature, you can definitely achieve this using Google Apps Script.

Here's a cool workaround: You can create your old letter template in Google Docs with the header and footer you want. Then, when you automate the generation of letters using Google Apps Script, you can make a copy of this template and populate it with the dynamic content you need. This way, each letter will have the desired header and footer.

Hello Chloe,

I'm a bit late, but be aware that Typeflow.us lets you do that. Easy set up, using Google Docs for template, in less than 3 minutes you can start generating PDFs. 

We currently offer a lifetime plan at 200$. It lets you generate as many pdfs as you want. 
Feel free to reach out to k@typeflow.us if you have any question!