That's mostly an opinion question, because it really depends. But that statement is probably false.
After a student graduates high school, they need time to plan on what they're going to do in the future, like <u>future career choices</u> or <u>college</u>.
The way you worded this is confusing but i think i get what you mean
It depends on what that child or person is doing after high school like if there going to college or if they're going to live in an appartment or not. I would say this is false because not every one does leave home after high school.