Hello, Maggie. When someone says this phrase, they are referencing a previous conversation or statement. It is used when someone you are talking to has had an event or experience, such as a job interview, a date, etc. The person asking this question wants to know if the event/experience went well or not. Example: Jane: I started my new job today. Amy: That's great! How did it go for you? It is also common to leave off the words "for you", and just say, "How did it go?", or even "How was it?"

It is common in American English. It is not a direct question. It is an idiomatic question. It means what was the outcome. For instance : How did your professor call go? A good answer is the call went well. A bad answer is the call went as we discussed it.I talked about all subjects we planned for.

Were the results good or bad?