The website you mentions may have added HTML links manually.
This is something I am trying to add to the homepage on my website.
Links can be added manually if you follow this path:

Admin Panel > Content > Content Boxes > Add a Box > Box Type > HTML > Show Box on > Show in categories

If you do not know HTML, you can use the following website to assist you:

- https://onlinehtmleditor.dev/

Good luck.