Muhammad (may peace be upon him) is considered special in Islam for several reasons, but to keep the answer short I'll limit myself to just 3:
1. Final Prophet: Muslims believe that Muhammad (may peace be upon him) was the last prophet in a long line of prophets that includes figures like Abraham, Moses, and Jesus (may peace be upon them all). He completed the prophetic mission by delivering the final revelation from God (Allah), the Quran.
2. Revelation of the Quran: The Quran, regarded by Muslims as the literal word of God, was revealed to Muhammad (may peace be upon him) over 23 years. It serves as a comprehensive guide for Muslims in all aspects of life.
3. Unifier: At a time of immense social and political fragmentation in the world, Muhammad (may peace be upon him) united everyone under the banner of Islam, emphasizing the worship of one God and establishing a community based on justice, equality, and faith.
His unification is still spreading rapidly, Islam is the second most practiced religion after Christianity. And in a hadith (teaching) of his, with regards to the end of times. He has taught muslims that Jesus (may peace be upon him - who in Islam is always referred to as a human and servant of God, not son of God), will return and both the true muslims & true christians will unify under the leadership of the son of Mary, against the evil forces of the world.