When a baby is born, sometimes the parents don't name it for a few days. When the baby is named, does it change? Or is it just a label assigned to the person that the baby is?
Similary, the Catholic Church was and is the one Church founded by Christ. Early on, this one Church, founded by Christ, was named the Catholic Church. Read St. Ignatius of Antioch's letter to the Smyrnaean's, around 107 A.D., in which he referred to the "Catholic Church" not as if he were coining the term, but in a manner in which he expected them to fully understand.
It says in paragraph 8, "Where the bishop is present, there let the congregation gather, just as where Jesus Christ is, there is the
Catholic Church."
See the entire letter here:
https://www.orderofstignatius.org/files/Letters/Ignatius_to_Smyrnaeans.pdf
The Coptics were a group in Egypt who were part of the Catholic Church, believing all the same things, etc. Around 451 A.D., the Coptics divided and some left the Catholic Church. They came back a few centuries later, then some left again. Some Coptics today are Orthodox and some are in full communion with the Catholic Church.
So, from your post, you think Jesus Christ was in error founding a Church (Matt. 1:18-19). And you know better than He did, right? In your opinion, there is no point to having a Church or authority or anything. You can be your own Pope and decide your own doctrines. Right?