It will be something like this
#include <stdio.h>
main()
{
int total_amount_seconds, hour, min;
printf("Give me the total amoumnt of seconds:\n");
scanf("%d", &total_amount_seconds);
hour = total_amount_seconds / 3600;
total_amount_seconds = total_amount_seconds % 3600;
min = total_amount_seconds / 60;
total_amount_seconds = total_amount_seconds % 60;
printf("There are:\nH:M:S - %d:%d:%d", hour, min, total_amount_seconds);
}