I think that the agency will provide you with sufficient training to get you started, Harry. They do not throw untrained teachers into the fray. You will find, however, that commercial language teaching in Japan (which I surmise that you are speaking of), especially at the entry level, does not require you to do more than follow the lessons in the textbook being used.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.