is it possible to write our own display statement and input statement
Certainly. How do you think the stuff from stdio.h was written? One cool thing about the standard C library is pretty much all of it can be written directly in C. I've actually implemented the standard C library before, and whole books have been written with that focus.
As far as writing your own output function without utilizing the standard library, you'll almost certainly end up using a system library like Linux's write() or Windows' WriteFile(). Sure, you could use assembly interrupts, but that's just crazy talk unless you're writing for a platform that for some reason doesn't expose a C interface for I/O.
On a side note, the linked book is one of my favorites. The code is a hard read, but you can learn a lot from it.
everyone is reading from dennis ritchie implementations of library function.similiar to this in java package concept they are writting import java.awt.event where action listner they r writting i dont know how a byte code is translated into program such a great thing that is