How can I add an Apple email address to an email client such as Evolution?
You can find the IMAP settings to use for your mail client at this support article.

Incoming mail server

Server name: imap.mail.me.com
SSL Required: Yes
Port: 993
Username: example@me.com (use your @me.com address from your iCloud account)
Password: Your iCloud password


Outgoing mail server

Server name: smtp.mail.me.com
SSL Required: Yes
Port: 587
SMTP Authentication Required: Yes
Username: example@me.com (use your @me.com address from your iCloud account)
Password: Your iCloud password