Good for you doing your research! You're a good mommy
I agree that 1 pound is tiny for a 3 month old. You've gotten some great advice & I don't really have anything to add. I agree with Maximo that it does help to hand feed sometimes. Sometimes they'll continue to eat on their own after eating a few bites from the hand. And you may need to feed off of a saucer or something very shallow since he's so small. Good luck with your little man. I love the name King!