Deletion in Singly Linked List in C++

#include< iostream>
using namespace std;

class Node
{
    public:
    int data;
    Node *next;
};

class LinkedList
{
    private:
        Node* head;
    public:
        LinkedList() { // constructor
        head = NULL;
    }
        void insert(int data);
        void display();
        void deleteNode(int data);
};

void LinkedList::insert(int data){

    Node* new_node = new Node();
    
    new_node->data = data;
    new_node->next = head;
    head = new_node;
}
void LinkedList::deleteNode(int delVal)
{
    Node* temp = head;
    Node* previous;
    
    if(temp == NULL){
        cout << "Can't delete Linked List empty" << endl;
        return;
        } // Case when there is only 1 node in the list 
        if(temp->next==NULL)
    {
        head = NULL;
        free(temp);
        cout << "Deleted: " << delVal << endl;
        return; 
        
    } // if the head node itself needs to be deleted
        if(temp->data==delVal)
    {
        head = temp->next; //changing head to next in the list
        cout << "Deleted: " << temp->data << endl; 
        free(temp); 
        return;
        } // traverse until we find the value to be deleted or LL ends 
        while (temp != NULL && temp->data != delVal) 
    { 
        // store previous link node as we need to change its next val
        previous = temp; 
        temp = temp->next; 
    }

    // if value is not present then
    // temp will have traversed to last node NULL
    if(temp==NULL)
    {
        cout << "Value not found" << endl;
        return;
        } // for node to be deleted : temp lets call it nth node // assign (n-1)th node's next to (n+1)th node 
        previous->next = temp->next;
    free(temp);
    cout << "Deleted: " << delVal << endl;
}
void LinkedList::display(){
    
    Node* node = new Node();
    node = head;
    
    cout << "\nLinked List : " ;
    
    //as linked list will end when Node is Null
    while(node!=NULL){
        cout << node->data << " ";
        node = node->next;
    }
    cout << endl;
    } 
int main() {
    LinkedList* list = new LinkedList();
    list->insert(1);
    list->insert(2);
    list->insert(3);
    list->insert(4);
    list->insert(5);
    list->insert(6);

    list->display();
    
    list->deleteNode(4);
    list->display();

    list->deleteNode(10);
    list->deleteNode(1);
    list->deleteNode(5);
    list->deleteNode(6);
    list->display();
    
    return 0;  
}