Legal issue

Hello Sir My name is Vikas Rajak Last year I cleared my 12th I got 98%. But didn't get a chance to take admission in college. Reason:- legal issue Can you please guide me? My mother is rajak [SC] And my father is Sharma [GENERAL] They got divorce after I was born. my mother left me to Nana- Nani's home And didn't come back so many years. Cause my birth certificate was a name of Vikas Sharma but my grandparents changed my name because some school teacher said to them maybe in 5th class Sharma to Rajak without any paper work. My adhaar card have name Vikas Rajak and all the marksheet after after 5th to 12th. My mother came back when I was in class 6th I guess. So I also have ration card with my mother that I have name Vikas rajak. But my mother never give it to me All the school journey I faced many problems related to paper work cause I had just a Adhaar card. Mother never gave her any doc. After 12th when it's time to take admission they asked the doc. But she clearly said you have a father to ask him and never try to ask me. I have completed 18 Years in January 2023 Now I'm legally adult. Now I have some Q can you please answer Should I make my other doc. Like Voter card pan card and other documents. With Vikas Rajak? •If yes Then don't you think it's illegal cause I just changed my name from Sharma to rajak without any paperwork?? •If No Then how can I clear this mess 🤔 Or should I back to my original "Sharma" Oh ! I'm so confused. I Don't want to waste my another year already I'm a burden on my grandparents.