Press the triangular button on controller.
You can't get mods for ps2 but you can on PC/any other computer maybe mac. There are cheats for ps2 though!
how to do kamekameha in gta dragon ball gt ps2
yes
NO
yes you can
poypoy abuhan
no
you cant you need a mod
No there is not one that I have seen
no
No you cant. sorry.
Im not sure probaly not