My dog is about to be put down?

My dog is about to be put down at 4pm because he has lime disease and his kidneys are failing, I took the day off from school and I'm just lying on my bed with him but I know he's going to die in a few hours and I don't know if I should go to the vet with my parents to put him down or not. I picked him out from his litter when I was in like 3rd grade, he's 8 and I'm 16 and he's my best friend