The Harry Potter series has always been heavy on the green screen and special effects. We know—big shocker, right?
In order to make sure we have all the wizards, spells, magical beasts, etc. from the novels, the filmmakers have had to go heavy on visual trickery and CGI, and this is definitely the case in the last installment of the series.
As in the previous films, we stick pretty closely to Harry's perspective. There's lots of action happening, particularly during the Battle of Hogwarts, so we do veer away from what Harry is seeing/doing from time to time, but mostly we're hitched firmly to Harry's wagon—you know, going where he goes, seeing where he sees, and just generally following his journey as it wraps up.