Input/output of transcript program files

It's a grade processing program. You want to add file input/output from code created with functions and pointers. In the 'Grades Processing Program.txt' file

1111 Gaga 10099897

2222 Nana 90898887

reach 3333 80 79 78 77

I wrote four grades, name, and score in three lines. And then

#define_CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#define SUB 4
char subname[SUB][6] = { "Korean", "English", "Mathematics", "C language"};
struct STUDENT {
    char id[5];
    char name[7];
    int score[SUB + 1];
    float avg;
    char alpha;
    int rank;
};
void input(struct STUDENT *stu, int PEOPLE) {
    FILE *fp;
    fp = fopen ("Sex Processing Program.txt", "w+");
    //char buffer[50];

    for (int i = 0; i < PEOPLE; i++) {
        fscanf(fp, "%s %s %d %d %d %d", (stu + i)->id, (stu + i)->name, &(stu+i)->score[0], &(stu + i)->score[1], &(stu + i)->score[2], &(stu + i)->score[3]);
        //fscanf(fp, "%s %s %d %d %d %d", stu[i].id, stu[i].name, &stu[i].score[0], &stu[i].score[1], &stu[i].score[2], &stu[i].score[3]);
    }

    /*for (int i = 0; i < PEOPLE; i++) {
        fscanf(fp, "%s\n", (stu + i)->id);
        fscanf(fp, "%s\n", (stu + i)->name);
        for (int j = 0; j < SUB; j++) {
            fscanf(fp, "%d\n", &(stu + i)->score[j]);
        }
    }*/

    fclose(fp);
} // Input function
void calculation(struct STUDENT *stu, int PEOPLE) {
    for (int i = 0; i < PEOPLE; i++) {
        (stu + i)->score[SUB] = 0;
        for (int j = 0; j < SUB; j++) {
            (stu + i)->score[SUB] += (stu + i)->score[j];
        } //Total score
        (stu + i)->avg = (float) (stu + i)->score[SUB] // mean
    }
} // Calculation function
void line() {
    for (int i = 0; i < 75; i++) {
        printf("-");
    }
    printf("\n");
}
void print(struct STUDENT *stu, int PEOPLE) {
    printf("\n");
    line();
    printf ("Grade Name: Korean, English, Mathematics, C Language Total Score Average Ranking\n");
    //fprintf(fp, "Grade Name, Korean, English, Mathematics, c Language Total Score Average Ranking\n");
    line();
    for (int i = 0; i < PEOPLE; i++) {
        printf("%6s %8s", (stu + i)->id, (stu + i)->name);
        //fprintf(fp, "%6s %8s", (stu + i)->id, (stu + i)->name);
        for (int j = 0; j < SUB; j++) {
            printf("%7d", (stu + i)->score[j]);
            //fprintf(fp, "%7d", (stu + i)->score[j]);
        }
        printf("%8d  %7.2f %5c  %4d\n", (stu + i)->score[SUB], (stu + i)->avg, (stu + i)->alpha, (stu + i)->rank);
        //fprintf(fp, "%8d  %7.2f %5c  %4d\n", (stu + i)->score[SUB], (stu + i)->avg, (stu + i)->alpha, (stu + i)->rank);
    }
    line();
} //output function
int main() {
    int PEOPLE;
    int ban_total[SUB + 1] = { 0 };
    double ban_avg[SUB + 1] = { 0 };

    printf ("How many people do you want to enter?" ");
    scanf("%d", &PEOPLE);
    struct STUDENT *stu = (struct STUDENT *)malloc(sizeof(struct STUDENT)*PEOPLE);

    input(stu,PEOPLE); //Enter
    calculation (stu, PEOPLE); //calculation

    for (int i = 0; i < SUB; i++) {
        for (int j = 0; j < PEOPLE; j++) {
            ban_total[i] += (stu + j)->score[i];
        } //Total score of subjects
        ban_avg[i] = (float)ban_total[i] /PEOPLE; //subject mean
    }

    for (int i = 0; i < PEOPLE; i++) {
        switch ((int)(stu + i)->avg / 10) {
        case 10: case 9: (stu + i)->alpha = 'A'; break;
        case 8: (stu + i)->alpha = 'B'; break;
        case 7: (stu + i)->alpha = 'C'; break;
        case 6: (stu + i)->alpha = 'D'; break;
        default: (stu + i)->alpha = 'F'; break;
        } //Grade
    }
    for (int i = 0; i < PEOPLE; i++) {
        (stu + i)->rank = 1;
    } //Initialize to seat 1
    for (int i = 0; i < PEOPLE; i++) {
        for (int j = i + 1; j < PEOPLE; j++) {
            if ((stu + i)->avg < (stu + j)->avg) {
                (stu + i)->rank++;
            }
            else {
                (stu + j)->rank++;
            }
        }
    }//Calculation of seats

    print(stu, PEOPLE);
    printf("                    ");
    //fprintf(fp, "                         ");
    for (int i = 0; i < SUB; i++) {
        printf("%-7d", ban_total[i]);
        //fprintf(fp, "%-7d", ban_total[i]);
    }// Total score by subject
    printf("\n");
    //fprintf(fp, "\n");
    printf("                    ");
    //fprintf(fp, "                         ");
    for (int i = 0; i < SUB; i++) {
        printf("%-7.1lf", ban_avg[i]);
        //fprintf(fp, "%-7.1lf", ban_avg[i]);
    }// Average by subject
    printf("\n");
    //fprintf(fp, "\n");
    //line(fp);

    //fclose(fp);
}