Debug Linked List

#include <stdio.h>
#include <stdlib.h>

struct node
{
    int data;
    struct node *add;
};

struct node *start=NULL,*temp,*New;

void create();
void display();

void main(){
    int n;
    scanf("%d" , &n);
    create();
    display();
}

void create()
{
    int n;
    char ch;
    if(start == NULL)
    {
        scanf("%d",&n);
        start = (struct node *)malloc(sizeof(struct node));
        start->data = n;
        start->add = NULL;
        temp = start;
        scanf(" %c",&ch);
        while(ch=='Y' || ch=='y')
        {
            scanf("%d",&n);
            New = (struct node *)malloc(sizeof(struct node));
            New->data = n;
            New->add = NULL;
            temp->add = New;
            temp = New;
            scanf(" %c",&ch);
        }
    }
    else
    {
        printf("\nList already created\n");
    }

}

void display()
{
    if(start == NULL)
    {
        printf("\nLink list not created, create a list first\n");
    }
    else
    {
        printf("\n");
        temp = start;
        while(temp!=NULL)
        {
            printf("%d ",temp->data);
            temp=temp->add;
        }
        printf("\n");
    }
}