Hi Sucker_Punch99,
To get Supreme Kai you'll need to be in Gohans D.U, when you begin fight Goten, after that a red dot appears were you would fight Videl but don't fight her, instead go to Kami's Lookout and fight Picollo, after the fight with him a red dot appears were you should fight Dabura, but don't fight him instead go to the Mountains located North East of the map, they are near the Big Island of Ice, there a scene with Vegeta titled 'Mountains', after your talk with Vegeta go and beat Dabura a red dot appears at Babidi's Spaceship enter it, now if everything went right Gohan will now go after Vegeta, but don't go to the red dot to fight him, go to the West City just to stand there, there's nothing there, but fly to the East and you should find some Dark Green Plains near there is a scene with Supreme Kai titled 'Plains', after your talk with him you will unlock him...
Now I'll tell you how to get Kibitoshin too...
After your talk with Supreme Kai and you unlock him go and fight Vegeta beat him, then go and beat Kid Buu, now there will appear a red dot to fight Broly, but don't fight him, instead go to Central City just to stand there, and now fly to the West you should find a Island, on the Island there's a scene with Kibitoshin, after that Kibitoshin will be unlocked too...
If this doesn't help, I don't know what will...
Sighs...