I’m guessing he has a warm snuggly space away from household traffic? If you haven’t already, make a nest for him. He cannot regulate body temperature so he must be kept warm. I think the best way is to place a heating pad, on LOW, covered by a towel and a soft blanket. Be sure to provide a “cool” spot for him to crawl if he gets too warm. I recommend getting him a soft squishy toy and put it in his nest. Wee kits usually snuggle up to the toy. It will give him comfort and extra warmth.
If he’s as young as you say, he will probably need to be bottle fed for a week. All you need to do is make a gruel. Put Goats milk and wet cat in a bottle and mix well. You could put some gruel in a bowl and see if he’ll eat that. If so, feed him that way. Feed him while he’s resting on his stomachs. Never feed them upright as you would a human infant.
KMR concentrate tends to give kits constipation and the liquid does the opposite. Some vets. don’t know about Goats’ milk but here in TDKland, we recommend Goats’ milk for kittens. Cats are lactose intolerant and can’t digest cows milk. Goats’ milk is full of nutrients, probiotics and gentler on their tummies. This can also regulate the poop. You can find it in the dairy section or the concentrate in the baking aisle. Mix the concentrate 1:1 with water or pedylite. If, at any time, they seem lethargic put a dab of Karo syrup or honey in their mouth.
Here’s another link with good information on raising your wee kits:
http://messybeast.com/handrear.htm
Good Luck
PG