By observing this book cover picture, I have written these sentences. Are these sentences grammatically correct and natural enough?

By observing this book cover picture, I have written these sentences. Are these sentences grammatically correct and natural enough?

? First of all, I need hardly say this book's cover is mesmerizing. Harry Potter, the spectacled guy, seems frightened as some evil skeletons glaringly trying to harm him. But the long bearded guy, Dumbledor, is saving Harry by casting a powerful spell through his wand. We can also see the writer's name, which is "J.K. Rowling" and the name of the book as well. To sum up, the book cover sends a chill down my spine and lures me to get this book.