My Prosperous Path from Catching Crabs

The male protagonist, Jason, has a cousin named Leo. Leo is the illegitimate son of Jason's father. Leo set a trap to cause a car accident involving Jason's mother and sister. The mother died, and the sister was seriously injured. Leo then pushed Jason and the female protagonist, Mia, from a high building to the ground. When Jason wakes up, he finds himself back to 1983. Realizing that he was trapped by Leo, Jason uses the same tricks to turn the tables on him. Then, he leads the whole village to prosperity by catching crabs.