HP: The Third Generation Black Demon King Unexpectedly Has Illness

[Harry Potter fan+no CP+Eagle House+protagonist's illness+crazy criticism+growth stream+using any means to achieve the goal+pursuing the highest level of magic]The protagonist Zhengtai will grow from ten to thirteen years old and then freeze.Why do others travel through the HP world and receive at least admission letters from owls, and some lucky ones even have prestigious family backgrounds and systems.But when it comes to myself, why is there only one "teacher" who treats him as a magical material/experimental assistant/life assistant?The sky collapses at the beginning.The only consolation is that there is also a diary beside him that can be used for conversation.Years later, as Vega stood at the top of the wizarding world, dragging his sickly body from his previous experiment, he smiled and wrote in his diary:"The Dark Lord... sometimes, he is one with the Savior/Capitalist/Spiritual Leader/PUA Master/Strongest Wizard!"The first volume will not enroll, there will be a large number of secondary settingsAs a fan of the novel version of HP Seven, excluding magical animals, cursed children, etc