How do I add custom fields, such as a phone number, to the registration form on the checkout page?

Question

1C-Bitrix

How to add a phone field, for example, to the registration form for unregistered users on the checkout page? I can't even find the file responsible for this.

Answer 1

If for an order, then here bitrix/admin/sale_order_props.php?lang=ru

How to register by phone number here