how to archive mac mail emails to an external drive

ICloud Drive is automatically set up on any current Apple device running the latest operating system. The Mac you activate last will create its own folder for the contents of its Documents and Desktop, and this will also sync. If you use iCloud Drive across multiple Macs then changes made to the Documents and Desktop files on both Macs will sync. This is a real file system, so you can create and save items to your own self-created folders, which is useful if you work across multiple devices. Changes applied to a copy of a file on one device will automatically sync across all your other systems. Open Files and you'll find iCloud Drive as a location.

On iOS devices, you access your iCloud Drive through the Files app. You can store documents, images and spreadsheets using iCloud Drive you can also keep files and folders up-to-date across devices, work on them, and access these items from anywhere. A PC must run Windows 10 to access iCloud for Windows. You need to be running iOS 13 or later or macOS Catalina or later on your iPhone, iPad, or Mac.

How to archive mac mail emails to an external drive