Could you tell me what are good ways to cure internal yeast infections in infants?

?? internal?? If you think you need to rid your infant of yeast in the GI tract, you are on a misdirected crusade and will fail. Yeast (candida albicans) is at least 5% of the dry weight of a healthy persons poo and is present everywhere. Babies occasionally have overgrowth in rashes or inside their mouth because of baby activities-eating all the time & sitting in poo a lot. Irritating yes but dangerous no.
Depends. What do you mean by internal yeas infection? Is it on the skin or systemic (blood, urine, etc). The best way to treat a skin yeast infection is to keep the baby's skin super dry, over the counter yeast medication creams also work.