Dear Prachanda,
Thank you so much for your query. I feel sorry to say that pre internship has been banned in Nepal.
However, you can do internship once you are eligible i.e. after your 4.5 years of medical education. Once you pass out from your college, you will have to contact NMC and get provisional registration and apply for the internship in Bir Hospital but you will have to go through entrance examination conducted by the hospital.
I hope these links will be helpful for you.
Places and Process For INTERNSHIP IN NEPAL http://www.xenomed.com/forums/intern...tal-nepal.html