apple id

Please see these reads:

Changing your Apple ID: https://support.apple.com/en-us/HT202667

What to do after you change your Apple ID: https://support.apple.com/en-us/HT204071

The second gets at the things that will be different after changing you Apple ID. In sum, a large number of things will be affected if you change your Apple ID.

About what?

In the discussion you posted a link to, that person had two Apple IDs, and wanted to change from one ID to the other ID. They weren't doing a name change on the existing ID. Your suggestion to do a name change should allow the OP of this post to retain everything.

I am confused. https://discussions.apple.com/thread/251133276?answerId=252152079022#252152079022

You figured it out. I was too brief. Thank you. I thought they both were trying to change their apple IDs. It still looks that way to me. See: https://discussions.apple.com/thread/251133276

If you change the email address of your existing Apple ID using the articles above, you shouldn't lose any data or access to your previous purchases.

You are welcome. The wording in that post is confusing.