There were Churches before the Catholic Church (CC), I do not believe the Apostles set up a Church as a central repository like the Catholic Church is today. I do believe that the Apostles followers started to setup a centralized church and it morphed into what the CC is today.
I have studied much Christian History and I found none of the claims that Catholics make here. There never was 100 percent unity and never 100 percent united behind one Church. Human nature being what it is would preclude that from being a possibilty, I don’t believe the claims of the modern Catholic apologist on the forum because history does not bear this out.
Anyway I don’t wish to get into an argument, it is what it is. Those who believe the CC is the end all of Christendom will always be that way.