G7X MKII track focusing and custom white balance

hi all,
is there any way i can do track focusing? I will be using the dive housing, so the touch screen is being disabled. is there any other way apart from manual focusing?

For custom white balance, instead of shooting at the white sanding bottom and then set the white balance in the camera, is there other ways like G12?

For G12, i can just hit one button, and the custom white balance is being set.