I bought the PC version in a sale to see what it was about after playing for a while.
It doesn't really attempt to explain the rules at all so I can see it being difficult if you had no previous experience. Also not helped by the fact that the AI is pretty terrible, so if you try to learn by watching it won't really work.
I'm happy to walk you through the basics if you (or anyone else) fancies giving it another try
Edit - and just to note, I'm from the UK and literally have no idea what the rules for American football are so I don't think any prior knowledge in that regard is necessary
That said you do have to have a good grasp of the basic rules of Bloodbowl before you start playing really to understand what you're doing and what would be a good move and what would be a bad move.