15 verses have
if
in Edition Clear Qur'an by Talal Itani / Al-Kahf (The Cave)

18:6Perhaps you may destroy yourself with grief, chasing after them, if they do not believe in this information.

18:20If they discover you, they will stone you, or force you back into their religion; then you will never be saved.”

18:24Without saying, “If God wills.” And remember your Lord if you forget, and say, “Perhaps my Lord will guide me to nearer than this in integrity.”

18:30As for those who believe and lead a righteous life—We will not waste the reward of those who work righteousness.

18:36“And I do not think the Hour is coming. And even if I am returned to my Lord, I will find something better than this in return.”

18:45And cite for them the parable of the present life: it is like water that We send down from the sky; the plants of the earth absorb it; but then it becomes debris, scattered by the wind. God has absolute power over everything.

18:46Wealth and children are the adornments of the present life. But the things that last, the virtuous deeds, are better with your Lord for reward, and better for hope.

18:57Who does greater wrong than he, who, when reminded of his Lord’s revelations, turns away from them, and forgets what his hands have put forward? We have placed coverings over their hearts, lest they understand it, and heaviness in their ears. And if you call them to guidance, they will not be guided, ever.

18:60Recall when Moses said to his servant, “I will not give up until I reach the junction of the two rivers, even if it takes me years.”

18:70He said, “If you follow me, do not ask me about anything, until I myself make mention of it to you.”

18:73He said, “Do not rebuke me for forgetting, and do not make my course difficult for me.”

18:76He said, “If I ask you about anything after this, then do not keep company with me. You have received excuses from me.”

18:77So they set out. Until, when they reached the people of a town, they asked them for food, but they refused to offer them hospitality. There they found a wall about to collapse, and he repaired it. He said, “If you wanted, you could have obtained a payment for it.”

18:96“Bring me blocks of iron.” So that, when he had leveled up between the two cliffs, he said, “Blow.” And having turned it into a fire, he said, “Bring me tar to pour over it.”

18:109Say, “If the ocean were ink for the words of my Lord, the ocean would run out, before the words of my Lord run out,” even if We were to bring the like of it in addition to it.