Alias
My Apple ID and the alias email are both on my phone and I can’t get rid of the alias so in conclusion I can’t access any emails and I’m unsure why ?
iPhone 11, iOS 14
You can't remove/change @iCloud.com, @me.com or @mac.com aliases.
iCloud - Create or change email aliases.
What happens when you try? Error message(s)? See if anything here helps.
Mail - If you can’t send email on your iPhone, iPad, or iPod touch
Mail - If you can't receive email on your iPhone, iPad, or iPod touch