Michi Uchiha is a shinobi from Konohagakure. He is also adopted by Tsunade. He does not know yet that he's adopted.
As a kid Michi's dream was to become an ANBU leader. He trains his whole life to become as strong as them, so he can protect the hokage. Him and Naruto Uzumaki live a similar dream to not give up and keep going. So he asks Tsunade to train him to get better.
As a young boy, Michi was an Orphan. He was very poor and didn't have a family. He slept near a store in Konoha. When Tsunade was walking out of a store with food, she saw him lying on the ground. As she approached him, he woke up frightened of her and said "Please don't hurt me". Tsunade told him "Don't worry honey, i'm not hurt you". He asked her "Do you have any food or money?" Tsunade told him "Come with me, i'll take good care of you honey". As she took him in, she trained him really hard. And became a hard training samurai.