Could you please let me know in shared code, what i should change?
I told you in the previous answer what has to be changed and how. Any place that now uses string must be changed to wstring, any place using char has to use wchar_t. Any class (GlobalScreenNotation) that reads ASCII (as string) has to be changed to read unicode (as wstring). Any stream / fstream objects must be changed to wstream / wfstream.

If you read something from a file as std:: string, there is no good way to convert it to wstring without producing garbage. You have to read it from the file as unicode if that's what the file contains. Even if the file contains standard ASCII, you can still read it as unicode and get the correct result, but not the other way around.

I am not going to write your code for you. You should get into the habit of writing new code to support unicode from the beginning. Never use char, use wchar_t, never use std:: string, use std:: wstring, use the unicode version of stream and string functions. If you don't know the unicode (wide character) versions of these functions, the CPlusPlus.com and CppReference.com web sites are good places to look.