The Islamic Republic has a political model of a republican system while maintaining an elite revolutionary Islamic council's absolute rule. That is why the country has a president and a supreme leader concurrently. The Supreme Leader of Iran maintains unquestionable power. The president of Iran is secondary to the supreme leader. The Supreme Leader is the unadulterated head of state, while Iran's president is the government's head.
The organization that elects the Supreme Leader of Iran is called The Assembly of Experts of Leadership. The president of Iran is selected through a popular vote. However, the Supreme leader determines who should run for president. The Supreme leader can be overthrown from office by the Assembly of Experts only. The president of Iran can be dismissed by the supreme leader.
The president of Iran monitors the cabinet, selects ambassadors and governors, and appoints the defense minister and intelligence chief, but he needs the Supreme Leader's approval. The president operates as the chief executive with limited powers, and the supreme leader is the absolute ruler.