Religion/ Name Change is affects during UpSC/Central govt jobs?

Hello Sir/madam, Recently I was following Jesus and Preaching of Bible due to my personal belief/wish; I want to change my religion and name legally as per Govt rules. Now I m Carrying Hindu- AdiDravidar(SC) community, by the way I am an IAS aspirant and still continue my preparation. Please provide me proper guidelines to change the mentioned change in legally. Actually I am not interested to change my name but when i did enquiry with Gazetted office they said name change is mandatory for Religion change. My Query is 1.) Is it affect any place during my upsc preparation 2) Which name i should use during applying any govt examination(Mostly asked 10th std name mentioned) 3) In my home only myself has been changed so, is it bring any problem to my parent and sister? 4.) Already I have acquired passport, voter id, Driving License, Pan card in my old name, how can i change it?. Sir, UPSC is my passion so i want to display my details with no flaws, Please kindly advice in proper way to approach the examination.