Is This Also Called Ninjutsu? Let Me Teach You!

I saw the ninjutsu teacher Oden Shinichi changing his gestures, flying his fingers, forming four seals very quickly, condensing chakra in his mouth, and shouted with great momentum: Fire Release: Fireball Technique! "Hoo" A gust of wind blew by, and Yiren looked at the small fireball 20 centimeters square that came out of his mouth! Confused? "Is this also called ninjutsu?" He felt like he could send this little fireball flying eighty meters away with just one slap! At this moment, he wanted to go up and tell Mr. Oden what ninjutsu was!