The counselor taught me how to stay calm when someone raised his voice.

raised 是动词 raise 的过去式，raise 的意思是"提高、举起"，在这里指"提高音量"。 his 是代词 he 的所有格形式，表示"他的"。 voice 是名词，意思是"声音、嗓音"。 raised his voice 是一个固定搭配，字面意思是"提高他的声音"，实际指"大声说话、叫喊"的行为。