Create an email address in iCloud Mail
If you set up iCloud using an Apple ID that doesn’t end with @icloud.com, you must create an @icloud.com email address on your iOS device, iPadOS device, or Mac before you can use iCloud Mail.
Note: If you set up iCloud using an Apple ID that ends with @mac.com or @me.com, you don’t need to set up an @icloud.com email address to use iCloud Mail. You already have an equivalent address that ends with @icloud.com.
On your iPhone, iPad, or iPod touch: Go to Settings > [your name] > iCloud, turn on Mail, then follow the onscreen instructions.
On your Mac: Choose Apple menu > System Preferences, then do one of the following:
macOS Catalina 10.15: Click Apple ID, click iCloud, select Mail, then follow the onscreen instructions.
macOS 10.14 or earlier: Click iCloud, select Mail, then follow the onscreen instructions.
If you don’t see onscreen instructions after turning on iCloud Mail on your iOS device, iPadOS device, or Mac, you already have a primary iCloud Mail email address. To create an email alias, see Use email aliases on iCloud.com.
After you set up your @icloud.com email address, you can use it to sign in to iCloud.com and your devices in addition to your Apple ID.