Is that what Mormonism teaches? I don't really know much about it.
Mormonism has many, many false teachings. They teach that Mormons are the only ones who have authority to baptize, give the Gift of the Holy Ghost, seal marriages to last for eternity, teach the "Plan of Salvation," etc.
This Church is the standard which Isaiah said the Lord would set up for the people in the latter days. This Church was given to be a light to the world and to be a standard for Gods people and for the Gentiles to seek to. This Church is the ensign on the mountain spoken of by the Old Testament prophets.
It is the way, the truth, and the life.
Marion G. Romney, Conference Report, April 1961, p. 119
LDS HYMN #27 "PRAISE TO THE MAN"
1) Praise to the man who communed with Jehovah! Jesus annointed that Prophet and Seer.
Blessed to open the last dispensation, Kings shall extol him, and nations revere.
chorus: Hail to the Prophet, ascended to heaven! Traitors and tyrants now fight him in vain.
Mingling with Gods, he can plan for his brethren; Death cannot conquer the hero again.
....
No, Joseph Smith isn't Christ according to Mormonism, but if you follow him and the Mormon church, you are believed to be following Christ.
Their church is the way;
their "Plan of Salvation" must be followed.