It sounds like you have an email alias that you would like to use. In Mail, you will have a "From:" field appear when you have an alias or additional email addresses. You can setup your email alias and send from the alias using these steps:
Set up an alias
- Choose Mail > Preferences, then click Accounts.
- Select an account, then click Account Information.
- Set up the aliases.
For an iCloud account: Choose Edit Aliases from the Alias pop-up menu to create the aliases in iCloud. For other accounts: In the Email Address field, enter the aliases, separated by commas (for example, email@example.com, firstname.lastname@example.org, email@example.com).
Send a message from an alias
In the New Message window, click the From pop-up menu and choose the email alias you want to use to send the message.
You may need to customize the header area to display the pop-up menu
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Thanks, It has solved half of the problem.
Now I have my email aliaises. But I want a "custom name" for each aliases. I have tried to add my custom names separated by commas in the fullname input but It doesn't work.
name, email alias
Example Inc, firstname.lastname@example.org
Accounting Exemple Inc, email@example.com
Is there way to do this ?