Difference between friend and fool in Korean
친구·바보

친구friend
A friend is a person you like and spend time with. In Korean, 친구 means a friend, usually someone close to your age. You can use this word when talking about school, home, playtime, shopping, or trips with people you know well.

바보fool
바보 means “fool” or “silly person.” People use it when someone does something careless, funny, or not smart. Friends or family may say it playfully, but it can sound rude if you say it seriously.
The difference
친구 means a friend, someone close to you. It does not mean a silly or careless person.