Izuku Yagi The Sword God

Izuku Yagi a kid who wanted to be a hero but because he was quirkless he was bullied by his sister and neglected and abused by his father, The number one hero All Might. Only his mother took care of him

One day his mother was fed up of her husband's abuse and neglect of his son, She gave a key to a house she was given by her family and told Izuku to go far away and train him hard, so hard until he surpasses his father.

She gave him a series of books mostly iaido and kendo books but there was a book all about a hidden power called Haki.

And this is Izuku's journey to becoming not just the number one hero but also the generatios hero's Sword God