[Dev-C++] problem writing data to file

[<Bah...@ao...>]

all i need to do is write  a few variables (int's) to a text file. the 
segment of data that makes the file looks like this :

        FILE * pFile;
        char buffer[] = "???";
        pFile = fopen (MonName, "w");
        fwrite (buffer , 1 , 100 , pFile);
        fclose (pFile);

MonName is the file's name. it turns out to be whatever the contents of 
MonName are

??? is what i need to  change

how would i make buffer[] represent :

cout << "The level is " << level << ", and the name is " MonName;
The level is 1 and the monster name is Red Dragon

also, not as important, but how would i have .txt be placed at the end of the 
file???