pointer used in argument list

I have two concerns I passed pointer as argument by value in the code below in
function initNode, addNode and several others the argument im thinking were pass by value. The changes to the link list were made successfully. I tried using same approach to changing insertFront and reverse member function but they did not change list. So i used a pointer to a pointer in parameter list and used the & operator and passed head the first node to list.
1) Why could i sucesfully init node and add node by pass by value and not reverse list or insertfront of list.
2)Usually in argument list with pointers you use & and variable name in argument list Im thinking the address is passed to function. What happens when the variable name is an address and the & operator is used (insertFront(&head,60))? Is the address of an address passed to function? Is that why I had to use pointer to pointer in parameter list.

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#include "stdafx.h"
#include<iostream>

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

class list
{
private:
	//    node *head= new node;

public:
	void initNode(node *head,int nodeData);
    void addNode( node *head,int newdata);
	void insertFront(node **head,int frontData);
	 node *searchNode(node *head,int key);
	 bool deleteNode(node **head, node *delptr);
     void reverse(node **head );
	 node *copyLinkedlist(node *head);
    void deletelinklist(node **head);
	void display(node *head);
};

void list::initNode(node *head,int nodeData)
{
		head->data = nodeData;
		head->next = NULL;
}

void list::addNode(node *head,int newdata)
	{
		using namespace std;
		node *current = head; 
		
	while(current->next !=NULL)
	 {
        
		 current = current->next;
     }
      if (current->next == NULL)
		 {
          node *newNode = new node;
		  current->next = newNode;
		  newNode->data = newdata;
		  newNode->next = NULL;
		 } 
	}

void list::display( node *head)
	{
		using namespace std;
		node *cur = head;
		while(cur)
		{
          cout<<"data = "<< cur->data<< endl;
		  cur = cur->next;
		}
	} 
void list::insertFront( node **head,int frontData)
	{
		node *frontNode = new node;
		frontNode->next = *head;
		frontNode->data = frontData;
		*head = frontNode;

	}

  node *list::searchNode(node *head,int key)
	{
		node *cur = head;
		node *nodeFound = cur;
		using namespace std;
		while(cur)
		{
			if (cur->data == key)
				{
				nodeFound = cur;
		        return nodeFound;
			    }
			cur = cur->next;
		}	
		   
		return nodeFound;
	}

bool list::deleteNode( node **head, node *delptr)
	{
		node *cur = *head;
		node *tempNextptr= cur;
		using namespace std;
		//cout<<"cur= "<<cur<<endl;
		//cout<<"*head= "<<*head<<endl;

		 while(cur)
		{
			if (cur == delptr)
			{
		        tempNextptr->next = delptr->next;
				if(cur == *head)
					*head = cur->next;
				
				delete cur;
				return true;
			}
	
			    tempNextptr = cur;
			    cur = cur->next;
		}

          return false;
	}

void list::reverse( node **head )
	{
       node *parent = *head;
	   node *me = parent->next;
	   node *child = me->next;
	  
	   using namespace std;	    
	   parent->next = NULL;
	   while(child)
	   {
		me->next = parent;
		parent = me;
		me = child; 
        child = child->next;
	   }
	     me->next = parent;
       	 *head = me;
	}



 node	*list::copyLinkedlist( node *head)
	{
		using namespace std;
		node *cur = head;
		node *newHead;
		
		while(cur)
		{
           node *newNode = new node;
		   if(cur == head)
			  newHead = newNode;

		   newNode->data = cur->data;
           newNode->next = cur->next;
		   cur = cur->next;
		}
		return newHead;
	}

/*	comparelinklist()
	{

	}
*/
void list::deletelinklist(node **head)
	{
		node *cur = *head;
		node *tmptr; 
		while (cur)
		 {
			 if (cur->next == NULL)
				 delete cur;
			 else
			 {
			   tmptr = cur->next;
			   delete cur;
			 }
			 cur = tmptr;
		 }
	}


int main()
{
	using namespace std;
    node *head= new node;
	node *newList,*newNode;
    node *found;
	bool remove;

  list lnklst;

	lnklst.initNode(head,10);
	lnklst.display(head);
    lnklst.addNode(head,20);
	lnklst.display(head);
	lnklst.addNode(head,30);
	lnklst.display(head);
	found = lnklst.searchNode(head,30);
	//cout<<"search node = "<< found->data<< endl;
	remove = lnklst.deleteNode(&head,found);
	//cout<<"head= "<<head<<endl;
    lnklst.display(head);
	lnklst.addNode(head,40);
	lnklst.addNode(head,50);
	lnklst.display(head);
	newList = lnklst.copyLinkedlist(head);
	cout<<"newlist"<<endl;
	lnklst.display(newList);
	lnklst.insertFront(&head,60);
	lnklst.display(head);
	cout<<"newNode list"<<endl;
    newNode = lnklst.copyLinkedlist(head);
	lnklst.display(newNode);

    //deletelinklist(&head);
	//display(head);

	cout<<"reverse list"<<endl;
    lnklst.reverse(&head);
	lnklst.display(head);

	if(remove)
	  cout<<"true"<<endl;
	else
	  cout<<"false"<<endl;

         
	cin.clear();
	cin.ignore(255,'/n');
	cin.get();

	return 0;
}
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