Being able to speak a language is not related to how smart you are. Anyone can learn how to speak any language. This is a proven fact by everyone in the world. Everyone can speak at least one language. Whether you are intelligent, or lacking some brain power, you are able to speak one language.
This proficiency is often attained by being immersed in an environment where the language is spoken regularly. In one's native country, constant exposure to and engagement with the language facilitates linguistic development. Notably, individuals who excel in English, for instance, often attribute their proficiency to attending English-speaking schools. However, it is not merely the school environment that fosters language skills. Rather, it is the continuous exposure to English speakers that plays a crucial role.