Difference between to call and to speak in Korean
부르다.·말씀하다

부르다.to call
부르다 means "to call." You use it when you say someone’s name or use your voice to get their attention and ask them to come. It is also used when you call for something, like a taxi.

말씀하다to speak
말씀하다 means “to speak” or “to say” in a polite, respectful way. You use it when talking to someone important or when speaking about what a respected person said. It is common with teachers, parents, grandparents, customers, and other polite situations.
The difference
This means to speak, usually in a polite way. It is about saying words, not asking a person to come or answer.