Merge primary email across all devices
iPhone has a primary email with iCloud and iMac has a different primary email with an alias iCloud email address attached. How to convert the iMac to match the iPhone primary email?
iMac 21.5″, macOS 13.7
From Mac sign out iCloud alia mail address ( it can be an an alias of your primary mail address of Apple ID signed in iPhone ) , and then sign in with primary apple id of iPhone , the two mail address ( Apple IDs ) will be exactly the same , make sure two devices should be on the same network .
Then follow the steps .
Sign in with the same Apple ID & password say example1@icloud.com on your iPhone & Mac and connect both with an usb cable .Overview of syncing your Mac and your devices - Apple Support
Click on finder > general > sync .
Let the bar be completely loaded .
Open your mailbox in iPhone .
Click on edit option on the up-right corner .
Click on “new mailbox” option on your down-right corner .
In the new mail box , in the name section enter your iCloud id say example1@icloud.com
And set your mailbox location as per you requirement (iCloud / gmail) - prefer iCloud
Then again click on edit , you will see your apple id , under it you will find an option of “new mailbox '’on your right corner > chose the name for your folder and add the mailbox location ( iCloud id )> click on save > finally click on done .
The folder is created in iPhone , from web browser ( mac ) open www.icoud.com in mail section in the bottom left corner click on refresh , the mail folders will be visible after few moments , then open IMAP account in mac Add or remove email accounts in Mail on Mac - Apple Support under iCloud section in the bottom click on drop down arrows all mail folders will appear .
For gmail accounts .
How to transfer mails from Mac to iPhone , even they are signed in with same Apple ID and password say example1@icloud.com
In iPhone go to settings > in password and accounts > click on add account you can select the desired account it could be gmail , enter gmail address and password and sign in it will prompt to check calendar , mail , notes , slide the box of them the apps data will start syncing .
There is an option fetch new data - push > in iPhone
You can connect the iPhone and Mac using usb cable and sync them Sync content between your Mac and iPhone or iPad over Wi-Fi - Apple Support
Sync content between your Mac and iPhone or iPad - Apple Support
The mails from Mac / iPhone will sync and take hours ( the fastest way is sync complete data ) , make sure all mails should be read ( no blue dots on each mail message ) Mark emails as read or unread in Mail on Mac - Apple Support