just kind of pry open his beak gently and put a little in there and maybe he will swallow some also you could put some warm water over some chick crumble and soften it up and try to put that in his mouth also
well I suggested sugar water because I've found it works for me she was already putting vitamins in the water the sugar water I have suggested saved multiple chicks of mine it gave them enough energy to start eating and drinking independently and their condition increased from there
It means he isn’t feeling well at all just keep giving him tlc he may pull through but like some people said some chicks just don’t thrive but keep on believing he will be okay just have lots of hope
you could also try sugar water I had a chick that was just drenched with water and almost died so many times but everytime I gave him sugar water he bounced back