Hosting its own email server takes a lot of time to setup, maintain and troubleshoot. I own my domain name and use it for emails since more that 20 years and used different ways to to it. There is a lot of good providers like Gmail, Protonmail but they can be expensive or you may not want to give them your data.
I've discovered Mail-in-a-box https://mailinabox.email/:
- Easy to setup
- Use common well known open source software
- Provide webmail (with GPG support), shared addressbook (and calendar)
- Well documented
Only drawback beeing is only support Ubuntu, but https://mailinabox.email/ adds support for Debian.
The best of two worlds !