Password to download pdf file

I’m designing a site with multiple products and each product has a detailed pdf document that customers can download, but I need to add a password in order for them to download the file.

I was wondering if there is a line of code I can use to prompt a password in order to download the pdf file for each product?

I know Webflow has a plan with a password option, but it looks like it’s for entire pages and not for downloading individual files.

Thank you,
Paolo