While being able to speak Japanese isn't absolutely crucial in order to survive in Japan, it does help and it often makes people more inclined to help you. Reading textbooks as well as exposing yourself to a lot of spoken Japanese can help you pick up some basic speaking skills. A great way to help you practice and increase your fluency is to find a Japanese speaking partner (preferably a native speaker or at least someone who has been speaking Japanese for several years) and speak Japanese with them on a regular basis.