There is no definitive answer to this question as it depends on various factors, such as the specific language, the individual's prior language learning experience, and their dedication and effort in practicing the language. In general, it can take anywhere from a few months to several years to become fluent in a new language. Consistent and regular practice, immersion in the language, and using various learning resources like language classes, textbooks, online resources, and language exchange programs can all help expedite the learning process.