Error fix

#include<stdio.h>
#include<string.h>
#include<malloc.h>
#include<conio.h>

typedef struct node
{
	char name[15];
	struct node *next;
}NODE;

void create();
void display();

NODE *insert(); 
NODE *delete_a();

main()
{
	NODE* start;
	int value=0;

	start=(NODE*) malloc (sizeof(NODE));
	do {
		printf("\n1.Create linked list");
		printf("\n2.Display created list");
		printf("\n3.Insert to the created list");
		printf("\n4.Delete from the created list");
		printf("\n0.Exit");
		printf("\n\n Enter Choice: ");
		scanf("%d",&value);
		printf("\n\n");
		
		switch(value)
		{
			case 1: fflush(stdin); create(start);
			break;
			case 2: display(start); 
			break;
			case 3: fflush(stdin); start=insert(start); display(start);
			break;
			case 4: fflush(stdin); start=delete_a(start); display(start);
			break;
			case 0: 
			break;
		}
	}while (value!=0);
}
void create(NODE *p)
{
	printf("Enter a name (End to stop): ");
	gets(p->name);
	if((strcmp(p->name,"end"))==0)
	p->next=(NODE*)malloc(sizeof(NODE));
	else
	{
	p->next=(NODE*)malloc(sizeof(NODE));
	create (p->next);
	}
}
void display (NODE *p)
{
	while(p->next!=NULL)
	{
	puts(p->name);
	p=p->next;
	}
}

NODE *insert (NODE *p)
{
	NODE *np, *nt;
	NODE *locate();
	char temp[15];
	printf("\nEnter the name before which u have to insert :");
	gets(temp);
	if ((strcmp(p->name,temp))==0)
	{
		nt=(NODE*)malloc(sizeof(NODE));
		printf("\n Enter name to be inserted:");
		gets(nt->name);
		nt->next=p;
		p=nt;
	}
	else 
	{
		np=locate(p,temp);
		if (np!=NULL)
		{
			nt=(NODE*)malloc (sizeof(NODE));
			printf("\n Enter the name to be inserted: ");
			gets(nt->name);
			nt->next=np->next;
			np->next=nt;
		}
		else
		{
			printf("\nName is not found");
		} 
	}
	printf("\n The Modified list is \n");
	return p;
}

NODE* locate(NODE*q, char *t)
{
	if (q->next==NULL)
		return NULL;
	
	else if(strcmp(q->next->name,t)==0)
		return q;
	
	else 
		return locate(q->next,t);
}

NODE* delete_a(NODE *p)
{
	NODE *nt, *np;
	char temp[15];
	printf("\nEnter the name to be deleted: ");
	gets (temp);
	if(strcmp(p->name,temp)==0)
	{
		nt=p->next;
		free(p);
		p=nt;
	}
	else