Kyle is an orphan, living with a distant family member who hates him. Through a series of seemingly miraculous events, he learns he's actually a wizard - from a highly respected magical family. He's accepted into a magical university that's divided into four houses. He learns he's (probably) the Chosen One of an ancient prophesy. He makes friends. He fights evil. Etc.
So, yes, this is rather blatantly inspired by Harry Potter, and one of the (genuinely) best parts of The Siren and the Sword is the afterword in which Cecilia Tan discusses her influences, and how she deliberately set out to adapt them in ways that interested her.
And, in a way, Siren - the first of the 'Magic University' series - is a distinct refinement of its, uh, predecessor. Siren is, as the series title might suggest, wholly about being a magic student. The overall plot is, accordingly, completely tangential; this is a book about late night pizza, course selection, cramming for finals and hooking up. It is a very niche area of world-building, but given the timeless appeal of wizarding school stories, a popular one. And it is fun - school stories give a method of infodumping that's inherently empathetic, much more so than, say, your typical 'wise old man exposits' format.