Assassin1St
you should start it by introducing the main character explaining how he got a system and is in the dragon ball world and go on from there here are some ideas first the mc is born on planet vegeta and he uses the system to help him train and get the grasp of fighting another idea is the mc is goku's brother and uses the system to be born with god ki and ultra instinct and heres some ideas for the personality of the mc imo he should be smart and calculative like he wont go out of his way to help somebody unless its benefiting him in some kind of way the opposite of goku idk if his system is op or not so i wont include any thing regarding the system and it would be best there is no FML or harem considering dragon ball isnt really focused on romance and it wouldnt fit the story of dragon ball