The Dandadan manga is indeed new. It has entered the manga scene recently and has managed to make a mark with its fresh concepts and engaging characters.
I don't know. There's no widespread knowledge or reliable source indicating whether Toriyama actually reviewed the manga guides. It remains a mystery for now.
To draw manga, practice basic shapes and anatomy. For the review, note the unique aspects of the manga, like its genre-bending or innovative plot. Mention if it stands out among similar works and if it has any flaws. Conclude with a recommendation based on your overall impression.
Well, usually such manga might have unique character designs and a complex plotline. The tentacle element could add an element of fantasy or strangeness.