I and a friend (both are not Apple users) had the same issue about 2 years ago. I gave up after trying different (non-Apple) platforms, IPs and phone numbers. He was applying to Apple internship and ended up borrowing a Macbook to set up his account.

And talking about why I wanted a new Apple account... My old account was created with stupid security questions (like, What is your favorite dish) as a second factor, which I believe Apple has long deprecated. I forgot my answers and that blocked certain functionalities. Resetting the security questions requires answering the questions...

I have a typo in my iCloud phone number.

I can't access anything without knowing exactly what I did wrong, presumably Apple never verified it when I created the account decades ago, but it's now part of the critical flow to log in.