How to display a hint for the selected shipping method?

Question

1C-Bitrix

Ordering is implemented on sale.order.ajax
When you change, for example, the delivery method, the data entry block is redrawn. I need to show a hint for the currently selected shipping / payment method in a certain place.
How is it implemented in bitrix? Those. it is clear that the description is stored in the properties of the selected delivery / payment method. But how to get the selected current value? In general, I have no idea about getting the current parameter IDs. And the order itself and the methods of delivery / payment.