After reading a few books on introduction to philosophy, I was recommended to read being and time by Martin Heidegger as I found temporality very interesting. Knowing that this book is one that many students of philosphy have a hard time understanding I decided to watch a few videos and read a few books about being and time before I even attempted to tackle Heidegger's book itself. The problem is that I cannot understand any of the videos I watch or any of the books or summaries I read. Clearly the introductory books did not prepare me, so my question is what do I start with? Is there any book that breaks down this philosophy and explains it in such a way that I can underestand? 
Thanks