A sensible choice is unfamiliarity.
unfamiliarity (with something) the fact of having no knowledge or experience of something
- He admits his relative unfamiliarity with this literature.
Oxford Learners Dictionaries
- There are weaknesses that suggest the author's unfamiliarity with standard academic practices.
Cambridge English Corpus
And an example showing a less academic, more social application: (bolding mine)
What is Culture Shock?
Culture shock is the feeling of disorientation experienced by someone
when they are suddenly subjected to an unfamiliar culture and way of
life. It can be caused by a range of things, both big and small, such
as unfamiliar greetings and hand gestures, strange food, difficult
language barriers, getting lost in a new city or making a cultural
faux pas because you didn’t know the local custom.
This unfamiliarity can lead to symptoms such as confusion,
anxiety, frustration, loneliness, and homesickness.