First of all, it's not beriberi. Athlete's foot, commonly known as tinea pedis, is actually itching and peeling off dead skin. Your situation is estimated to be that walking is a normal phenomenon, as long as it doesn't crack. If you really want to treat it, buy some vitamins to eat. Vitamin e has a bottle and pills. I can only treat beriberi with dyclonine, but it still doesn't work. It is best to keep your feet clean. Don't wear leather shoes and airtight shoes often.