How is it possible that only 300 million people speak English?

There doesn't seem to be more than 400 million people in America. There are probably no more than 250 million people. English-speaking countries mainly use English as their mother tongue, and their daily lives are also English-speaking countries, so there are not many. Many countries have the concept of bilingualism. For example, English is very popular in many African countries, but they don't say that they are English-speaking countries, and English is only used as a second language. Just like South Africa, Mandarin is not the only language of Chinese. Hakka dialect, Minnan dialect, Fuzhou dialect and so on are all Chinese. Ordinary people in China can understand Mandarin. In this way, it is not enough for the usage rate of Chinese to reach1300 million, but it should be more.