Hi there ​@kaizenakira, 

My name’s Scott and I’m a Technical Support Specialist here at Zapier. I hope you're having a great day so far—happy to lend a hand here.

When it comes to password protection on a PDF, this is normally set at the time of the PDF creation. If needed after, this would normally need a conversion or edit of the file itself. Once that is done, you should be able to use that to send this to your other service, to have the password protection on file access.

As Zapier's built-in Formatter tool doesn't include file encryption capabilities, this will need a third party tool to get this properly set. That said, this is a good idea for a future addition, and I will be bringing this up with my team for a possible feature request in our formatter. 
 

That said, looking at our apps, I do see that a common app used for this would be the PDF Blocks app. This is specifically designed for PDF operations and includes a "Protect PDFs with a password" action usable in your Zap directly. 

I have more on this app here: https://zapier.com/apps/pdf-blocks/integrations
 

There are also other good options in our app directory here that could work for the use case but would need research to see whats best for you: https://zapier.com/apps/categories/documents

Some common examples are: 

• PDF4me: Offers document protection along with conversion and PDF/A compliance
• PDF-app.net: Provides encryption alongside HTML/DOCX to PDF conversion
• XSS PDF Solutions: Includes protection as part of comprehensive PDF management

I hope this helps, but if you have any other questions or need further clarification, let me know.

Thank you for the information, I really appreciate it.