gotoxy() is a function developed by Borland for Turbo C. It was never standard C to begin with, so to get your program back to standards and up to date, try using: SetConsoleCursorPosition()
Here's another usefull link

other things that are non-standard in your program are:
#include <conio.h> Just delete it
clrscr(); Click here for alternatives
getch(); . Use getchar(); instead if you're just using it to pause the program