Little Big Man (1970) and Dance with wolves (1990) . I saw them many times when I was a kid. It made me understand early that the adult world would be tough. I was also amazed with the landscapes. https://www.imdb.com/title/tt0065988/?ref_=nv_sr_srsg_0 https://www.imdb.com/title/tt0099348/?ref_=nv_sr_srsg_0
Un Prophète (2009 by J. Audiard). A weird gangster movie that makes you realize that even in the worst situation, even if you reached the bottom, there is a path to get out... https://www.imdb.com/title/tt1235166/?ref_=nv_sr_srsg_0
Ghost Dog (1999). I was obsessed for months by the music and by the scene when Withaker steals the car... https://www.imdb.com/title/tt0165798/?ref_=fn_al_tt_1