HELP

#include<string.h>
#include<stdio.h>
#include<stdlib.h>
#include<ctype.h>
#include<windows.h>

struct patient{
char pid[6];
char fname[20];
char lname[20];
char fullname[50];
char gender[2];
char age[3];
char address[30];
char city[20];
char state[20];
char zipcode[6];
char apptype[20];
char doctor[30];
char date[9];
char location[40];
}patientdets,patienttemp;

int choice;
FILE *fpatient;
char *token;

//MAIN MENU
void menu();
//SUB MENUS
void patmenu();
void appmenu();
//PATIENT MENU
void addpat();
void viewpat();
void searchpat(){};
void editpat(){};
void deletepat(){};
//APPOINTMENT MENU
void addapp(){};
void viewapp(){};
void searchapp(){};
void editapp(){};
void deleteapp(){};
//STRUCTURE FUNCTIONS
char *getPatientID();

COORD coord={0,0};
void gotoxy(int x,int y)
{
 coord.X=x;
 coord.Y=y;
 SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE),coord);
}

int main ()
{
    menu();
}

void menu ()
{

        do
        {
            system("cls");
        printf("---------- MAIN MENU ----------\n");
        printf("(1)PATIENT\n(2)APPOINTMENT\n(3)EXIT PROGRAM\n");
        printf("CHOICE:");
        scanf("%d",&choice);
        switch (choice)
        {
            case 1:
                {
                    patmenu();
                    break;
                }
            case 2:
                {
                    appmenu();
                    break;
                }
            case 3:
                {
                    exit(0);
                }
            default:
                {
                    printf("PLEASE ENTER A VALID NUMBER!\n");
                }
        }
        }while(1==1);
}

void patmenu()
{
    do
    {
    system("cls");
    printf("---------- PATIENT MENU ----------\n");
    printf("(1)ADD PATIENT\n(2)VIEW PATIENT\n(3)SEARCH PATIENT\n(4)EDIT PATIENT\n(5)DELETE PATIENT\n(6)RETURN MAIN\n(7)EXIT PROGRAM\n");
    printf("CHOICE:");
    fflush(stdin);
    scanf("%d",&choice);

        switch (choice)
        {
        case 1:
            {
                addpat();
                break;
            }
        case 2:
            {
                viewpat();
                break;
            }
        case 3:
            {
                searchpat();
                break;
            }
        case 4:
            {
                editpat();
                break;
            }
        case 5:
            {
                deletepat();
                break;
            }
        case 6:
            {
                return;
            }
        case 7:
            {
                exit(0);
            }
        default:
            {
                printf("PLEASE ENTER A VALID NUMBER!\n");
            }
        }
    }while(1==1);
}

void appmenu()
{
    system("cls");
    int choice;
    char pid;
    printf("---------- PATIENT MENU ----------\n");
    printf("(1)ADD APPOINTMENT\n(2)VIEW APPOINTMENT\n(3)SEARCH APPOINTMENT\n(4)EDIT APPOINTMENT\n(5)DELETE APPOINTMENT\n(6)RETURN MAIN\n(7)EXIT PROGRAM\n");
    printf("CHOICE:\n");
    scanf("%d",&choice);
    while (1==1)
    {
        switch (choice)
        {
        case 1:
            {
                addapp();
                break;
            }
        case 2:
            {
                viewapp();
                break;
            }
        case 3:
            {
                searchapp();
                break;
            }
        case 4:
            {
                editapp();
                break;
            }
        case 5:
            {
                deleteapp();
                break;
            }
        case 6:
            {
                return;
            }
        case 7:
            {
               exit(0);
            }

        }
    }
}

char *getPatientID()
{
    static char pid[6];
    printf("Enter Patient ID:\n");
    scanf("%s",pid);
    return pid;
}

char *getFirstName()
{
    static char first[20];
    printf("Enter First Name:\n");
    gets(first);
    return first;
}

char *getLastName()
{
    static char last[20];
    printf("Enter Last Name:\n");
    gets(last);
    return last;
}

char *getGender()
{
    static char gender[2];
    printf("Enter Gender:\n");
    gets(gender);
    return gender;
}

char *getAge()
{
    static char age[3];
    printf("Enter Age:\n");
    gets(age);
    return age;
}

char *getAddress()
{
    static char address[50];
    printf("Enter Address:\n");
    gets(address);
    return address;
}

char *getCity()
{
    static char city[10];
    printf("Enter City:\n");
    gets(city);
    return city;
}

char *getState()
{
    static char state[10];
    printf("Enter State:\n");
    gets(state);
    return state;
}

char *getZipcode()
{
    static char zipcode[6];
    printf("Enter Zipcode:\n");
    gets(zipcode);
    return zipcode;
}

void addpat()
{
    int i=0;
    char selection;
    char z[30]=" ";
    fpatient= fopen("TP038123","a");

    if (!fpatient)
        {
        printf("File does not exists!\n");
        }
    else
    {
        system("cls");
        fflush(stdin);
        strcpy(patientdets.pid,getPatientID());
        fflush(stdin);
        strcpy(patientdets.fname,getFirstName());
        fflush(stdin);
        strcpy(patientdets.lname,getLastName());
        strcat(z,patientdets.lname);
        strcat(patientdets.fname,z);
        strcpy(patientdets.fullname,patientdets.fname);
        fflush(stdin);
        strcpy(patientdets.gender,getGender());
        fprintf(fpatient,"%s-->%s-->%s\n",patientdets.pid,patientdets.fullname,patientdets.gender);
    }
}

void viewpat()
{
    int getc(void);
    char buffer[1024];
    char *token;
    char tok[4]="-->";

    fpatient=fopen("TP038123","r+");
    if (!fpatient)
    {
        printf("ERROR:FILE CANNOT BE OPENED!\n");
        fclose(fpatient);
    }
    else
    {
        if(feof(fpatient))
        {
            printf("ERROR:END OF FILE!\n");
            fclose(fpatient);
        }
        else
        {
            fread(&buffer,sizeof(patientdets),1,fpatient);

            token=strtok(buffer,tok);

            printf("Patient ID:\tFullname:\tGender:\n");
            while(token!=NULL)
            {
                printf("%s\t",token);
                token = strtok(NULL,tok);
            }
            fclose(fpatient);
        }

    }
    char cont;
    fflush(stdin);
    printf("\n\n");
    printf("space to cont...");
    scanf("%c",&cont);
}