to broaden / expand / widen one's horizons / mind
/bɹˈɔːdən ɛkspˈænd wˈaɪdən wˈʌnz hɚɹˈaɪzən mˈaɪnd/
phraseto expand one's knowledge, experiences, or perspectives, often by exploring new places, ideas, or cultures, with the aim of gaining a broader understanding of the world