If you have registered for it just log in with username and password, you don't need a code or anything.
If you haven't registered you need to register and pay. If you paid for a live review you get online review access for 30 days--starting the day you log in and open up the online review.
I think the videos add up to around 20 hours. However, you may pause and rewind the video to keep up which will make it take longer.
You can take the Q review practice test 6 times. I like the practice test I think, haven't taken NCLEX yet.