During biblical times, what happened to humans who had never heard of God?

Hi! I grew up in the church, but never really paid attention. Recently, I have been inclined to take my faith seriously but before I could do that, I wanted to make sure to reconcile biblical truths to my personal curiosity.

During biblical times, how could someone who has never heard of God be saved? For example, they were geographically disadvantaged to hear of Yahweh or eventually, the Gospel?