Finished the Manga but don't get it

I caught up, but I just ended with one idea that probably means I didn't learn shit from the manga. Basically Musashi was always a genius but his ego just clouded his judgement. If that's the case, then what about people who aren't geniuses? Idk man, it seems I'll have to reread again. Tried reading the book of five rings but couldn't understand his way of writing.