The Catholic churches must be different than regular Christian ones.
There are no “regular Christian” ones. Catholicism is a denomination of the religion, and was one of the original two main churches (other being Russian Orthodox). I’m guessing you mean others like the Protestant churches.
Christianity has been around longer than cathicism, and the bible even warns against organized religion. (No, really.)
By organized I mean having a governing body controlling and dictating what the smaller pieces do. It says each individual church should run itself. And that’s not The only trait of Catholicism that the bible condemns either but that’s a debate I don’t have the energy for right now.
But saying Catholicism is The original Christian church is just straight up false.