It looks like a Green Sunfish to me, due to the shape of the body, mouth, and gill plate. With the angle and hands in the way, it is hard to tell for sure, because it does look a little stockier than the average Green Sunfish I see, so it could be a hybrid green sunfish/bluegill.
I'm not a fish ID expert or anything, but most of what I assume are pure Bluegill have pretty pronounced vertical bars, short/round bodies, small mouths, and a roundish gill plate that doesn't extend very far back.
Green Sunfish lack the distinct vertical bars, are longer and less round, have bigger mouths and have a more oval shaped gill plate, and the spot on the gill plate usually has a halo around iit.
Then you'll catch a fish that seems to have some characteristics of both. I assume these are hybrid green sunfish/bluegill. I've posted one below as an example.
Photo 1 is a typical bluegill
Photo 2 is a typical green sunfish
Photo 3 is what I figure to be a hybrid (Broken pattern, bluegill shape but with a bigger mouth and more oval shaped gill plate)
I'm not a pro, so please tell me if I'm mistaken in any of my identification assumptions.