Is she drinking on her own? That's more important than food. If you put sugar in the water, it will elevate her blood sugars just as food does, and she won't starve.
Your hen is very sick. Chances are she is dying, and dying chickens do not feel like eating. Continue for the rest of today giving her sugar water. Lets see if she is improved tomorrow to maybe want to eat some scrambled egg. If she isn't improved tomorrow, you need to face the reality she may be dying.