The term for words with the same spelling but different pronunciation and meaning is heteronym.
Heteronyms are a special type of homograph: the written forms are identical, but the words are pronounced differently and have different meanings. For example, “lead” can mean to guide, pronounced “leed,” or the metal, pronounced “led.” Other familiar examples include “tear,” “wind,” “dove,” and “bass.”
The related terms are easy to mix up. A homograph shares spelling, while a homophone shares pronunciation; neither term alone requires both conditions found in a heteronym. “Pair” and “pear,” for instance, are homophones but not homographs. “Bank,” meaning a financial institution or the side of a river, is commonly treated as a homograph, though its pronunciation stays the same.
Heteronyms often arise because English spelling preserves older forms while pronunciation changes, or because words entered English from different historical sources. Stress can also distinguish them, as in “record” used as a noun versus “record” used as a verb.