The NW school is a good source but it depends on how much you want to deep dive into the subject. If your aim is just to "speak the same language" and understand what is happening, it is fine. If your aim is to handle the accounting part on your own, you should definetly do a face-to-face course or an intership to put your hands on the financial statements ina safe enviroment.
Where are you going to start your company? Every country has his own detailed rules about accounting, you should consider it before buying a course.
Hope it helps,