I've been searching for a few days. The website "documents" have displayed nothing and I couldn't find anything on this forum about it either, but I'm obviously doing something wrong since everyone else seems to know how to access the ftp feature and I don't even know where it is. Can someone tell me how to do this? If it helps, I'm using filezilla for ftp management.

FTP is a way to access webspace/servers directly and not a Zenphoto feature. Please try a web search on FTP (File Transfer Protocol) in genera and contact your host about the data to access your webspace via FTP.

You create an account on Filezilla that connects to your website with the initial folder being the one where you installed Zenphoto. Then you can use Filezilla to copy images and albums to your installation's albums folder.