Widget for X products

it would be nice if customers could somehow know beforehand that there is a promotion on that product, otherwise they only find out when the purchase is already underway. The promotion is useful if it encourages the purchase, otherwise it becomes a loss. If the customer already wants to buy my product, why should I give them a gift? They will buy it anyway. It would be nice if somehow the gift (product y) could be seen, thus giving the customer the possibility to see it when looking at the page. At the moment, I wouldn't know where it is best to display it, maybe in the upper corner of the photo. (We need to understand how to display the item; if it is a gift, it should be shown, if it is a discount when purchasing the item, no, we can also display it normally with a pop-up; if there are multiple gifts, only the notification of one gift should appear…) It would require some study.