I set up a alias email address in iCloud but how do you see the mail in that account ? I followed the instructions from search how to see it on your iPhone which did’t work
If its an alias, then the mail is the same as your default account. An alias is just that, another address that is tied to your default email address. FYI you should post in a related forum, such as Apple Card, Apple Music, Apple Pay, iCloud as this is not MacBook Air related