In the Documents tab of your Folia home, you'll see a gear icon on each file. You will also see this gear in the toolbar when a document is open. Tap on the gear to access Document Options. Inside Document Options you can rename, export, or delete the document form the folia.
Exporting the document allows you to save the document outside of the Folia app, such as to the device's local storage or to a cloud service. You can save these documents as annotated or flattened PDF or as the original document, free of annotations. You can also export a summary of all of the annotations in a document.
Be advised, if you delete a document from Folia, it cannot be undone. The document will be deleted permanently.