EML files are simply saved email messages, but because macOS and many systems don’t open them by default, users often think they need technical skills or email software like Outlook. In reality, that’s not necessary. The simplest way to view EML files is by using a dedicated EML viewer that works in a read-only manner and doesn’t require any setup or configuration.

For example, MacSonik EML Viewer Pro is designed for non-technical users. You just add the EML files, and the software displays the emails exactly as they were received. You can read the message body, see sender and receiver details, and preview attachments without changing any data or settings. There’s no need to understand email servers, file formats, or metadata.
Read more: https://www.macsonik.com/eml-viewer/