How can I change the ‘From’ Email Address for all emails.

I believe you’ll be able to update the email address/alias here:

Settings > [Your Name / AppleID] > iCloud * > Mail

* Having accessed iCloud, scroll to the very bottom of the page: Mail is the final item in this list

You do have Composing. It is the main section under which Always Bcc myself is located. However, you don’t have Default account. After rereading your first post, I think that it may be tied to the fact that both of your accounts are Apple email accounts. Didn’t .me accounts become iCloud accounts? If so, you just have two different aliases for the same account.

I could very well be wrong about this. Do you get the same emails in both accounts? I freely admit that I don’t know anything about Apple’s email accounts.

I assume that this is the only account that you have on the iPad and that’s why default account doesn’t show, but I’m not sure about that. I have three email accounts so I see Default Account in my settings.

I’m not sure how to change the identifier/alias of the account to show iCloud. I asked for help in another area of the community where you have to be a higher level user to have access. Hopefully someone else will join in to help.

If you are running iOS 14, Go to Settings>Mail>Default Account and change it in there. You have to swipe down to get to Default Account.

Did you swipe down far enough? Default account is the last thing in the list under Composing. Is your iPad company owned or do you have a profile on it?

You’re very welcome.