Satan is known as the accuser of the brethren. His aim is to have others join him in cursing God:
Job 1:11 But now stretch out your hand and strike everything he has, and he will surely curse you to your face.
God didn’t quite rise to the bait. Knowing that Job would indeed keep his faith:
Job 1:12 The Lord said to Satan, ‘Very well, then, everything he has is in your power, but on the man himself do not lay a finger.’
So who caused Job’s distress? Satan tried to claim God did it, even though the agent of evil was Satan.
Despite that, God still took responsibility, as He had allowed the disasters:
Job 2:3 Have you considered my servant Job? There is no one on earth like him; he is blameless and upright, a man who fears God and shuns evil. And he still maintains his integrity, though you incited me against him to ruin him without any reason
Then Job lost his health, again through the direct actions of Satan (even if God allowed it).
Job believed the series of calamities came from God, but he heroically refused to curse God for it all:
Job 2:10 ‘Should we accept only good things from the hand of God and never anything bad?’ So in all this, Job said nothing wrong.
Satan’s scheme had failed.