Bitrix filtering of goods and trade offers?

Question

1C-Bitrix

Earlier I already asked the question https://qna.habr.com/q/1105110
I solved it, but another problem arose. What if I need to filter the products themselves, and not trade offers?

Now my filter is set like this

if(in_array($key, $FILTER_OFFERS_PROPERTY_CODE)){
                    if(!empty($value)){
                        $filters['filters']['OFFERS']['PROPERTY_'.$key] = explode(',', $value);
                    }
                }else{
                    if(!empty($value)){
                        $filters['filters']['PROPERTY_'.$key] = explode(',', $value);
                    }
                }

And in fact, if a trade offer code comes in, I select it there, but how can I filter it already by product.
That is, how to understand or what I now need to filter by product.

In the properties of the category, I set the filter parameters, but I don’t understand how to connect it.