Who can see your knowledge
What is private, and what your clone will repeat.
Your knowledge sources are not published anywhere and are not visible to other Personify users.
But your clone answers from them. Anyone who can reach your clone can ask questions whose answers draw on that material. Treat anything you upload as something a stranger could eventually be told.
The practical rule
If you would not be comfortable explaining it to somebody who turned up at your website, do not add it.
Removing something
Delete the source on the Knowledge step. It stops being used straight away. Confirm by asking about it in Test Arena.