I can’t make a new account on my iPhone

I honestly don't know what you mean when you say "BIU".

WCYCI?

Okay, now that we have ceased playing around with things the other doesn't understand, this article explains how to create a new Apple Account --> How to create a new Apple Account - Apple Support

If you see a 'Could Not Create Apple Account' or 'Could Not Set Up iCloud' message, read this article --> If you see “The maximum number of free accounts have been activated” - Apple Support

*Why can't you create it?