In my view, it is like this. Four areas I am going to talk about. China mainland; Hong Kong and Taiwan and Macau.
In china mainland, different towns there have diverse dialects. When they went to junior high school. They start to learn mandarin together. After that mandarin is the common language to communicate. In the city, they start mandarin at primary school or when they were born. They learn mandarin from their parents
In Hong Kong. Cantonese and traditional Chinese writing same as Macau. But Macau may also speak
Portuguese I am not very sure.
In Taiwan. Traditional Chinese writing and Taiwanese. (very close to mandarin sounds but have a different way to say some words. I like it .sounds better than original mandarin)
To answer your question. Yes, there are many languages.
