I'm not sure specifically as I haven't read it. It could potentially be about various things. Maybe it's a novel centered around a mysterious black deck box with some sort of special significance in a fictional world, perhaps related to magic, a game, or a secret society.
The SCP Foundation is purely fictional. It's a collection of imaginative and often creepy stories and characters that are made up for entertainment purposes and have no basis in reality.
To find the 'keter black deck box novel', start with specialized book search engines. These can help you locate both physical and digital copies. Another option is to join book - related forums or groups and ask fellow enthusiasts if they know where to get it. Social media platforms can also be useful. Post a query about the novel and see if anyone has any leads on where it can be purchased or borrowed.
SCP 106's origin is rather mysterious. It is an extremely dangerous and malevolent entity within the SCP Foundation's lore. Some believe it has existed for a long time, perhaps emerging from some sort of dark dimension or abnormal space.