It's a alternate universe or whatever where goku wasn't the only sayian sent to earth as a youth. At first the differences seem small but will get more different drastically.
After the events of the World Martial Arts Tournament and the wedding of Goku and Chichi the planet Earth is once again in peace as the newly weds settle down and have a son named Y/n.The boy like his father is power hungry as he grows up in the world of Martial Arts and trains to be just like him,much to the disbelief of his mother who wants him to become a scholar,and along the way he meets his father's friends and may even his future significant other during his very own World Martial Arts Tournament.There will be hardships in Y/n's life but if he's the son of Goku then it shouldn't be anything he can't handle.