In the Pandora myth, Prometheus stole fire from the gods before Pandora was created.
Greek myth presents Prometheus as a benefactor of humanity. After Zeus withheld fire from mortals, Prometheus concealed some divine fire and brought it to humans, allowing them to cook food, make tools, work metals, and develop civilization. Zeus responded by arranging a punishment for both Prometheus and humanity.
Prometheus was chained to a mountain, where an eagle repeatedly devoured his liver. For humanity, Zeus ordered the creation of Pandora, the first woman in Hesiod’s account. The gods endowed her with various qualities, and Zeus sent her to Epimetheus, Prometheus’s brother.
The fire episode and Pandora episode are connected in Hesiod, but they are separate parts of the myth. Pandora did not steal fire, and Prometheus did not open the jar. Those actions are sometimes merged in modern retellings.