Hi
@Jasmine Fields 
Welcome To BYC. I'm sorry to hear about your loss.
Do you have any photos of the sick chickens?
How old are they?
What type of medicines did your neighbor give you?
From your description it sounds like you are dealing with a respiratory disease. Infectious Bronchitis, Mycoplasma, Infectious Coryza and ILT are a few of the more common ones. Without testing, it's hard to tell sometimes which one you have.
http://edis.ifas.ufl.edu/ps044
You can try treating with injectable Tylan50 which can be found at feed stores like Tractor Supply. Dosage is .20ml per pound given 2times per day for 5days. I recommend that you give it orally. Antibiotics will only treat secondary infections, so they may not be effective with certain illnesses. If you have vet care, that is always best.
For swelling of the eyes - you can flush them with saline or sterile water, try to remove any discharge or pus that you see. Apply an ophthalmic ointment like Terramycin or similar to the eyes to help with infection.
It is important, as you mentioned to keep them drinking. If you have them add some poultry vitamins to their water. For food, ideally their normal poultry food - you can try wetting it to make a mash. Chopped egg or tuna would also be good.
fwiw - respiratory illnesses are contagious and can spread rapidly through a flock. Birds that have been sick, recovered and those exposed are considered carriers of the illness for life. I you happen to lose anymore, getting some testing performed by your state diagnostic lab would give be a good idea.