Sadly, there's no public knowledge about whether Bryce Hall has an affinity for reading fanfiction. Fanfiction can be a very personal form of entertainment. Some people love it for the freedom it gives to expand on existing fictional universes, while others might not be interested. Without Bryce Hall saying anything about it, we can only wonder if he's part of the fanfiction - reading community or not.
Since I don't know the specific Bryce Love Story, it's hard to say who the main characters are. But surely Bryce would be one of the main characters. There could be a love interest, perhaps named something like Emily or James, who plays a crucial role in Bryce's love story.
As I don't know the specific 'girl on Bryce Hall story', I can't say who the girl is. It could be a girl from his personal life, like a friend, a romantic interest, or someone he worked with on a project. Without more details, it's impossible to identify her.