Dragon Ball: Travel to Yamucha

Qiu Jiu traveled from the earth to Yamcha in Dragon Ball and obtained the mission system. As long as you complete the tasks issued by the system, you can get rewards. There is a time room. There is a Dafa. There is a magic weapon. With the help of the system, can Qiu Jiu change Yamcha's original destiny? The author is a newbie, please bear with me and give me some advice, thank you This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.