I have seen some very lengthy lists on here in answer to this, including various types of antibiotics and dressings, vitamins and other supplements, etc.
I have used the peroxide or Betadine or Neosporin on a chicken that I keep for myself, occasionally. For the chickens I keep BluKote and use a poultry dust or powder as a preventive for lice/mites; it's usually a pyrethrin/permethrin blend. You can use plain Neosporin in an injured eye. You can make your own saline for washing wounds after the initial peroxide or Betadine cleansing. I also use Sevin 5% garden dust for flies and lice/mites but would probably not buy it for this unless there was an infestation, which I've never had; I just happen to have a canister of it. I also keep pelletized lime and Stall-Dri for those times that the deep litter needs some odor/fly/moisture control, more than adding shavings. I would probably not buy anything else ahead, myself.
For wounds there is a product sold for horses named Scat (or something like that) that keeps flies from laying eggs in wounds which can be handy, and another called vet wrap (a similar product is sold for people) that is handy if you just need to keep a dressing on something. Hopefully you will never have to deal with this serious of a wound, though. To stop bleeding, a product that works well is also sold for animals, don't know the name; in an emergency you can use a styptic pencil, flour or corn starch, and plain old pressure.