Yahweh continues speaking to the unfaithful people of Israel.
The people did not literally go to Sheol, the world of the dead. Instead, Yahweh is indicating by exaggeration that the people were willing to go anywhere to find new gods to worship. (See: rc://en/ta/man/translate/figs-hyperbole)
After trying so hard, the idolators found they still had strength to keep going. Here “hand” equals “strength” or “capacity.” (See: rc://en/ta/man/translate/figs-metaphor)