@Chenn2016
Sorry to hear about your duck.
I agree, that her current health situation should be addressed as quickly and effectively as possible, then treat the underlying cause of her problem. Have you gotten tube feeding supplies yet?
She really needs them soon or I'm afraid she'll pass.
For tubing, you could try your local health pharmacy, maybe a wildlife rehabilitator, or you could get some aquarium tubing for fish tanks. You'll also need either a 35ml/60ml syringe, which could be found at most feed stores. Either some game bird feed crumble, or more preferably some Kaytee Exact Baby Feeding formula which could be found at a pet store like
Petco/Smart. And lastly, you'll need a scale.
Sounds like a lot, I know, but if you can't take her to a vet she needs to be rehydrated, then given some food asap.