You kinda have to see them.
But since you haven't to understand the story:
- Harry potter created an army to defeat voldemort.
- Draco malfoy and his family are have sided with voldemort (but you can tell Draco doesn't want to be there)
- Harry and Ginny Weasley like each other.
- Ron and Hermione like each other.Love/hate relationship very cute
- Harry Ron hermione have left hogwarts(it's not safe and they need to kill voldemort)
-Snape killed dumbledore therefore is the new headmaster of hogwarts. Harry at this stage really really hates him:
and what the deathly hallows are about? Harry potter trying to kill voldemort and vise versa.
How he Harry trying kill him? By killing horcruxes.
What are horcruxes? Since voldemort died and came backto life he put a spell on certain items then scattered them in very hard places to keep him alive, which if destroyed would kill him.
Harry,Ron an hermione are trying to find all of them and hopeully kill voldemort.
How's voldemort trying to kill him? He has the most powerful wand ever created, some sort of deathly hallows wand. The wand only shows it's true powers to it's owner (just remember that it's important in the movie)
That's pretty much what you missed and a whole lot more I just can't think atm haha.
I just watched part 2 today at the cinemas. It was AMAZING. But if you want to really userstand the story watch the other movies. It'll make alot more sense