Opening up the listing shows you the 'Enhanced Media' section right on the overview tab, under the listing description.
Clicking on the gear icon will allow you to modify the link. By and large, if what you have setup in CORE ListingMachine is what you want, then you don't need to change the links. If you do change the links, your modification will permanently override the links sent over from CORE Listing Machine (Circlepix.)
The links here are displayed on your kvCORE website, on the details page for that listing.