There are different aspects of God's will. It isn't God's will that anyone sins or goes to hell but people have free will.

There are times when God causes something to happen or prevents it from happening.

(Exodus 4:21 NIV) The LORD said to Moses, "When you return to Egypt, see that you perform before Pharaoh all the wonders I have given you the power to do. But I will harden his heart so that he will not let the people go.

(Exodus 7:2-4 NIV) You are to say everything I command you, and your brother Aaron is to tell Pharaoh to let the Israelites go out of his country. {3} But I will harden Pharaoh's heart, and though I multiply my miraculous signs and wonders in Egypt, {4} he will not listen to you. Then I will lay my hand on Egypt and with mighty acts of judgment I will bring out my divisions, my people the Israelites.

(Exodus 14:4 NIV) And I will harden Pharaoh's heart, and he will pursue them. But I will gain glory for myself through Pharaoh and all his army, and the Egyptians will know that I am the LORD." So the Israelites did this.

(Exodus 14:19-29 NIV) Then the angel of God, who had been traveling in front of Israel's army, withdrew and went behind them. The pillar of cloud also moved from in front and stood behind them, {20} coming between the armies of Egypt and Israel. Throughout the night the cloud brought darkness to the one side and light to the other side; so neither went near the other all night long. {21} Then Moses stretched out his hand over the sea, and all that night the LORD drove the sea back with a strong east wind and turned it into dry land. The waters were divided, {22} and the Israelites went through the sea on dry ground, with a wall of water on their right and on their left. {23} The Egyptians pursued them, and all Pharaoh's horses and chariots and horsemen followed them into the sea. {24} During the last watch of the night the LORD looked down from the pillar of fire and cloud at the Egyptian army and threw it into confusion. {25} He made the wheels of their chariots come off so that they had difficulty driving. And the Egyptians said, "Let's get away from the Israelites! The LORD is fighting for them against Egypt." {26} Then the LORD said to Moses, "Stretch out your hand over the sea so that the waters may flow back over the Egyptians and their chariots and horsemen." {27} Moses stretched out his hand over the sea, and at daybreak the sea went back to its place. The Egyptians were fleeing toward it, and the LORD swept them into the sea. {28} The water flowed back and covered the chariots and horsemen--the entire army of Pharaoh that had followed the Israelites into the sea. Not one of them survived. {29} But the Israelites went through the sea on dry ground, with a wall of water on their right and on their left.