Christ came from Hebrew Massaiah which is translated into Greek 'Christos' and then re-introduced as 'Christ' in English. So, 'Christianity' came from translation of a translation. Now tell me, if your name is translated twice, can anyone recognize you? Should you be called by that name?
Let me break it down for you, from the perspective of truth.
Every Religion is made up. There is no God. It matters not how the fictitious text that one group of people came to be compares to how another fictitious text came to be.
Arguing that there is only one religion, is like arguing that Capitan Picard could kick Capitan Kirks ass.