Google Doc saved as PDF will not keep formatting when transferred back to Google Doc for editing?

I’m working on creating editable templates. For this I’ll create it in Google Docs and save as a PDF. I’ll then transfer the file as a PDF for the end user. They will then be instructed to open back up in a Google Doc that they can then edit/personalise it.

Issue is that when I convert back to the Google Doc, the imagery is all gone and the text formatting is all over the place and illegible.

Sharing via the normal Google way won’t work for what I’m needing to do. So any advice would be amazing!

Thanks in advance for the help