External fungal infection is just a symptom of systemic fungal infection/overgrowth. You can get rid of the external problem, but if you don't fix the diet, it will most likely return anyhow.
Simple things that I know of for foot fungus might be soaking them in water with baking soda OR apple cider vinegar OR hydrogen peroxide OR Iodine [this can be applied topically too!] OR collidial silver OR tea tree oil. I also heard that Vicks Vaporub applied onto the foot fungus and left on overnight can kill it. Remember to wear socks if you do this.
As to diet, has to be low carb, low sugar, low starch ... to stop feeding the fungus. Then anti fungals to kill them while you're starving them. [You'll know they're dying because when they die they release mycotoxins [myco=fungal toxins=poisons] and you'll feel like crap for awhile!] Take anti fungals like apple cider vinegar, garlic, coconut oil [caprylic acid], olive leaf, oregano oil, food grade Iodine .... to name just a few. Avoid foods known to have fungus like blue cheese, peanuts, corn. Take probiotics or eat fermented foods or both.
You can't get rid of it totally, but you DO want to bring back the balance in your body.