For high-school students, start with guardianship and daily support
A minor's independence is also limited by guardianship, housing acceptance, leave permission and medical authority. Strong language ability does not remove the need to identify who is responsible after class, how family is contacted and who handles night problems.
For university students, test operational ability
Booking a room is not the same as running a study life. Test reading course terms, arriving on time, budget tracking, roommate conflict, payment scams and finding formal medical and insurance help when unwell.
Age also changes course and housing fit
School minimum age, minor accommodation, transfers and activity permissions can differ. University students should not assume they can book every residence or rental; use the school or provider’s written rules.
Build independence in trainable stages
Practise arrival day, first-week commute, one independent purchase and one formal help request before adding weekend arrangements. Completing those tasks is more reliable than judging someone as abstractly 'mature'.