Why can I not change my Apple ID into one with @icloud.com?

[FatherJack1980]

Quite a few years ago I created an AppleID (very probably on my iPhone 4); I had an email account at live.com which I used - so my appleid ends with @live.com.

However, I want to change that into @icloud.com - and I finally found a way to register an @icloud.com address, however it will not allow me to let the @icloud.com be the default one and @live.com as a backup.

There's no family sharing going on, not iTunes rentals or purchases, I have an iPhone 4 and a Windows computer but perhaps going to buy a Mac one, etc. I added this screenshot which hopefully will clarify what it is I'm trying to achieve but Apple seems to make so bloody difficult

 

[Synergie]

You can change it to the iCloud and it’s even saying that in your screenshot. Just that once you do, you won’t be able to change it back to any other email address in the future.

 

[FatherJack1980]

You can change it to the iCloud and it’s even saying that in your screenshot. Just that once you do, you won’t be able to change it back to any other email address in the future.

If you are perhaps referring to the red text, then that's the text I get after I click "continue"; I can click on "Continue" until the end of the world and I'm always getting that annoying red text and doesn't allow me to continue to change my Apple ID from @live.com to @icloud.com

Sorry for asking the community this, but is there any portion of the Apple homepage where I can ask someone, preferably an Apple employee about iCloud and how to change the Apple ID? Or is there any site on the web where Apple employees answer questions for non-technical people?