How do you access a pointer of a class nested in another class

 class pairList {
  private:
    int value1, value2;
    pairList *nextEntry
    pairList *reverseM(pairList *prev);
  public:
    pairList(int v1, int v2, pairList *next) : value1(v1), value2(v2), nextEntry(next) {}
    int getFirstValue() { return value1; }
    int fetSecondValue() { return vlaue2; }
    pairList *getNextEntry() { return nextEntry; }
    pairList *reverseM();
    pairList *search(int val);
}; 

 class grades {
  private:
     pairList *allGrades;
     float mean, stdDev;
     bool meanValue;
   public:
     grades() {}  // start with empty class
     void addGrade(int studentID, int grade);
     float average();
     int getScore(int studenID);
     int getZScore(int studentID);
     pairList *getAllGrades() { return allGrades; } // I added this line
};

 void grades::addGrade(int studentID, int grade)
 {
   grades *access = this;
   
   if(access->getAllGrades()->getNextEntry() != NULL)
     access->addGrade(studentID, grade);
   else
     access->getAllGrades()-getNextEntry() =
       new pairList(studentID, grade, NULL);   // I get an invallid lvalue in assignment here
 }

 pairList *readForwardList() {
  int inputval1, inputval2;
  pairList *front = NULL;
  
  cout << "enter ID no: " ; cin >> inputval1;
  cout << "\nEnter grade: "; cin >> inputval2;

  while(!cin.eof()) {
    front = new pairList(inputval1, inputval2, front);
    cout << "Enter ID no: ";  cin >> inputval1;
    cout << "\nEnter grade: "  cin >> inputval2;
   }
   cout '\n';
   return front->reverseM();
 }

  int main() {
    grades *theGrades, *tmpGrades;
    int i, j;

     theGrades->gatAllGrades() = readFowardList(); // error here! how do you do it correctly?
     tmpGrades = theGrades;
     while(tmpGrades->getAllGrades() != NULL) {
        i = tmpGrades->getAllGrades()->getFirstValue():
        j = tmpGrades->getAllGrades()->getSecondValue();
       cout << i << ' ' << j << ' ';
       tmpGrades->getAllGrades() = tmpGrades->getAllGrades()->getNextEntry();  // error, lvalue
    }
    cout '\n';
   // delete here
 return 0;
 }

     access->getAllGrades()->getNextEntry() =
       new pairList(studentID, grade, NULL);   // I get an invallid lvalue in assignment here

intList *intList::addList(intList * newList){
    if(this == NULL){                   // if current list is empty
        return(newList);                //   return newList
    }
    intList *tmpList = this;            // append newList to this list
    while(tmpList->nextEntry != NULL)
        tmpList = tmpList->nextEntry;
    tmpList->nextEntry = newList;
    return(this);
}

int main(){
using namespace std;
intList *theList = NULL;
int i;

    for(i = 0; i < 8; i++)              // initialize list {0..7}
        theList = theList->addList(new intList(i, NULL));

 struct addr {
  char name[30];
  char street[40];
  char state[3];
  unsigned long int zip;
 }

 
  struct emp {
    struct addr address;  // nested structre
    float wage;
 } worker;

grades::addGrade((int studentID, int grade){
    allGrades = new pairList(studentID, grade, allGrades);
}

class grades {
// ...
     grades() {allGrades = NULL; mean = 0.; stdDev = 0.; meanValue = 0;}
// ...

class grades {
  private:
    pairList *allGrades;               // list of grades
    float mean, stdDev;
    bool meanValue;
  public:
    grades(){allGrades = NULL; meanValue = false;}
    ~grades();                         // destructor
    void addGrade(int studentID, int grade);
    void reverseM(){allGrades = allGrades->reverseM();}
    void showGrades();
};

grades::~grades(){
pairList *tmpList;
    while(allGrades != NULL){
        tmpList = allGrades;
        allGrades = allGrades->getNextEntry();
        delete tmpList;
    }
}

 grades *theSubject = NULL; // global scope
....
void inputGrades() 
{
   int inputval1, inputval2;
   // grades theSubject;  local scope

     cout << "Enter studentID no: ";  cin >> inputval1;
     cout << "Enter grade: ";  cin >> inputval2;

      while (!cin.eof()) {
        theSubject->addGrade(inputval1, inputval2);
        cout << "Enter studentID no: ";  cin >> inputval1;
        cout << "Enter grade: ";  cin >> inputval2;
      }
     cout << '\n';
 }

 int main()
 {
    //grades *theSubject;  local scope

    inputGrades();

   // mean();

   // deleteList(theSubject->getAllGrades());
return 0;
 }

grades *theSubject = NULL;

int main()
{
// ...
    theSubject = new grades;
// ...
    theSubject->addGrade(...);
// ...
}

grades theSubject;

int main()
{
// ...
    theSubject.addGrade(...);
// ...
}

pariList * allGrades(NULL);
pairList * allGrades = NULL;