How to display the number of remaining products on the site?

Question

1C-Bitrix

Hello!
Now the site has an unloading from 1C:UT.
It looks like this:

Further, in the sales offers, it is clear that there is one product of a certain size:

To display the available quantity of the product, I did this in catalog.element:

<?echo 'Доступное количество: ';
   echo $arResult['CATALOG_QUANTITY'];
?>

Displays 0. Which, as I understand it, is taken from the available quantity of goods from the first picture.
Actually a question. How can I display the number of remaining products on the site, if their number is in trade offers?