What does Christianity, Islam or Judaism say about this? a sin or previllege?

[niko]

If an 18 year old boy leave his house, family, friends forever and go to another country and live and work by his own without informing his family?

 

[DrDeanCrosby]

That would be extremely cruel causing your family tremendous grief and worry.If you feel it necessary you can inform your family of your general location without giving them specific contact details.

 

[david]

Sin