What should I do if I am laughed at and have no culture?

If I know today, why should I know? It's too late to regret. If someone laughs at it, let him laugh at it. Don't care. Speak less if you don't understand what others say, and don't answer if you don't understand. Fortunately, you are studying art now, study hard, become an artist in the future, and have time to read more books that suit you.