adding shared folders to ios files

Hi, I don’t know if I’m missing something. I’ve shared a folder with my girlfriend to help her with her work. She’s writing a document on my iPad Pro but she also has a iPad mini, I want her work to sync across devices so I’ve shared a folder with her and put her document in it. How can I add this folder to her files app so she can access it when she needs? It currently loads up in a browser window which isn’t as easy. I also want to be able to find the document within word but it seems hidden.

Thanks

Rob