can 12 week old kitten miss one meal?

I had to leave my kitten at home alone for a few hours so i put him some food before I left
I think I put him food for about two meals
but there was still 2hours left until his meal time but he started eating anyway

When i came back about 5 hours later he had finished his plate of food
So now its his meal time but he wont eat he doesnt seem hungry and walked away from the plate
So would it be alright if he skips this meal and just eats the next? Or must I wake up in the middle of the night to give him food?

I want ti set him meal times but I'm worried if he doesnt eat anything for about 12 hours would it hurt him?

12 hours is a long time for a kitten. Can you leave some food out for him overnight?

yes I can, but problem is, when I do that he's not hungry the next meal and won't eat
he leaves some of his food and eats it later when i'm leaving it out

Also another question when can I switch him to eat 3 meals a day instead of 4?