Liked-List to Convert Char to UPPERCASE

[LibLife]

Hello,
I am trying to convert a character sentence to an to UPPERCASE using Linked-List queue.
Below is my code, but it's not compiling, and I can't figure out the problem.
Please help me.

//Headerfile
#ifndef LINKEDQUEUETYPE_H
#define LINKEDQUEUETYPE_H

#include<iostream>
using namespace std;


struct nodeType
{
	char info;
	nodeType * link;

};

class linkedQueueType
{
public:
	void initializeQueue();
	bool isEmptyQueue();
	linkedQueueType front();
	linkedQueueType back();
	void addQueue(const linkedQueueType& newItem);
	linkedQueueType();
	~linkedQueueType();
private:
	nodeType * queueFront;
	nodeType * queueRear;
};

#endif // LINKEDQUEUETYPE_H


//.cpp file
#include "linkedQueueType.h"
#include<iostream>
using namespace std;

//Add Queue
void linkedQueueType::addQueue(const char& newItem)
{
	nodeType * newNode;
	newNode = new nodeType; 
	newNode->info = newItem;
	newNode->link = NULL;
	if (queueFront == NULL)
	{
		queueFront = newNode;
		queueRear = newNode;
	}
	else
	{
		queueRear->link = newNode;
		queueRear = newNode;
	}
}

//IsEmpty
bool linkedQueueType::isEmpty()
{
    return(queueFront == NULL);
}

//IsFull
bool linkedQueueType::isFull()
{
    return false;
}

//Initialize Queue
void linkedQueueType::initializeQueue()
{
    nodeType * temp;

    while(queueFront != NULL)
    {
        temp = queueFront;
        queueFront = queueFront->link;
        delete temp;
    }

    QueueRear = NULL;
}

//Front
linkedQueueType linkedQueueType::front() const
{
    assert(queueFront != NULL);
    return queueFront->info;
}

//Back
linkedQueueType linkedQueueType::back() const
{
    assert(queueRear != NULL);
    return queueReal->info;
}

//Default Constructor
linkedQueueType::linkedQueueType()
{
    queueFront = NULL;
    queueRear = NULL;
}

//Destructor
linkedQueueType::~linkedQueueType()
{
    initializeQueue();
}

//main.cpp
#include "linkedQueueType.h"
#include <ctype.h>
#include<iostream>
using namespace std;


int main()
{
    char ch;
    linkedQueueType queue;

    cout << "Please enter a sentence: \n";
    cin.get(ch);

    while (ch != '\n')
    {
        toupper(ch);
        queue.addQueue(ch);
    }

    cout << "Queue Elements: ";

    while (!queue.isEmptyQueue())
    {
    cout << queue.front() << " ";
    queue.deleteQueue();
    }
    cout << endl;

    return 0;
}

[integralfx]

Return Value
The uppercase equivalent to c, if such value exists, or c (unchanged) otherwise. The value is returned as an int value that can be implicitly casted to char.

http://www.cplusplus.com/reference/cctype/toupper/

char ch;
cout << "Please enter a sentence: \n";
cin.get(ch);

You're trying to fit a string in a character which isn't going to work. Use std::string and loop through each character.