Hi
@Alex022 
Welcome To BYC
Can you post some photos of him and the breast bruise as well?
Can you tell us bit more about him - how old is he?
The bruising on the breast - do you know the cause - injury, fighting, fall, etc.?
Do you think the foot is from any injury as well?
How long has he been like this?
It sounds like he is failing from your description. As mentioned above, provide him with some poultry vitamins (Poultry Nutri-Drench is good). Focus on getting some fluids into him. After he is hydrated, then make some wet feed, chopped egg or tuna available.
For the foot, you can soak it in epsom salts or diluted betadine to help reduce swelling. After it's dried, apply Vetericyn or triple antibiotic ointment. Place him on clean dry bedding.
Hopefully we can see the breast bruising as well. Antibiotics may be needed to help heal the foot, but if he has breast injury - injectables like Penicillin may not be the best to use.
Hopefully
@Eggcessive will give her input. Tylan50 can be given orally and is usually found at the feed store. It
may help with infection, but is used more for respiratory infections. (I'm just trying to think what may be available on local levels that you can get quickly).