C++ Class ‘undeclared identifier”

This is really frustrating, I’ve tried multiple variations of my class and constructor, sifted through pages of google results and other questions on this site but I can’t figure it out. I believe the error is something simple that I’m overlooking.

Error code:

1>main.cpp(60): error C2065: 'Student' : undeclared identifier
1>main.cpp(60): error C2146: syntax error : missing ';' before identifier 'newStudent'
1>main.cpp(60): error C3861: 'newStudent': identifier not found

student.h

#ifndef STUDENT_H
#define STUDENT_H
class Student {  
    private:
    static const int SIZE = 7;         // initial size of the array
    int *Students;                     // Students will point to the dynamically allocated array
    //int numStudents;                   // number of students currently in the list
    int rosterSize;                    // the current size of the roster
    int student_id;
    string name;
    string classification;
    public:
    Student();                         // constructor; initialize the list to be empty
    ~Student();
        void set_id(int);
        void set_name(string);
        void set_class(string);
            int print_id();
            string print_name();
            string print_class();
    //void enrollStudent();              
    //void Print(ostream &output) const; // print the list to output
};
#endif

student.cpp

        #include <iostream>
#include <string>

#include "student.h"

#define PROMPT "class> "
using namespace std;

Student::Student(){    // declared here right?
    student_id = 0;
    name = "";
    classification = "";
}

Student::~Student(){
    //delete Student
}

void Student::set_id( int i ){
    student_id = i;
}

void Student::set_name( string n ){
    name = n;
}

void Student::set_class( string c ){
    classification = c;
}

int Student::print_id(){
    return student_id;
}

string Student::print_name(){
    return name;
}

string Student::print_class(){
    return classification;
}

main.cpp

#include <iostream>
#include <string>
#include "student.h"

#define PROMPT "class> "
using namespace std;


//**** Implement Error Handling ****\\

enum errorType {
    UNKNOWN_ERROR,
    INPUT_ERROR,
    HANDLER,
    NUM_ERRORS
};

// error messages

string errorMessage[NUM_ERRORS]= {
    "Unknown Error\n",
    "Input Error\n",
};

// error handler

void handleError(errorType err) {
    if(err > 0 && err < NUM_ERRORS)
        cout<< "Error: "<< errorMessage[err];
    else cout<< "Error: "<< errorMessage[UNKNOWN_ERROR];
}

//**** END Error Handling ****\\



void getInput() {


    int id; string n, c;
    cin>>id>>n>>c; 
    //cout<<id<<"-"<<n<<"-"<<c<<endl;
    Student newStudent();      //****WORK DAMN U!
    //set_id(id);
    //print_id();

    return;
}


int main() {
    //Student newStudent();   /* <-- why doesn't this work?!*/
    string input = "";
    bool finished = false;

    cout<<PROMPT; // prompt the user
    while(!finished) {
        if(input!="") cout<<PROMPT;
        cin>>input;
        if(input=="enroll") {
            cout<<PROMPT<<"Enroll student:"<<endl;
            getInput();
        }
        else if(input=="drop") {
            cout<<PROMPT<<"Enter ID:"<<endl;
        }
        else if(input=="roster") {
            cout<<"This will print formatted list of students"<<endl;
        }
        else if(input=="quit") {
            finished=true;
        }
        else handleError(errorType(1));
    }
}

Just as a note, my professor said adding #include student.h
to my main.cpp would fix my issue. OBVIOUSLY NOT because I included it in my student.cpp SO THANKS. ಠ_ಠ

tl;dr here is a smaller barebones version that gets same errors:

#include<iostream>
#include<string>
#define PROMPT "class> "

using namespace std;

class Student {
private:
int student_id;
string name;
string classification;
public:
Student();    // constructor
~Student();
void set_id(int);
int print_id();
};

Student::Student(){
    student_id = 0;
    name = "";
    classification = "";
}

Student::~Student(){
//delete Student
}

void Student::set_id( int i ){
    student_id = i;
}


int Student::print_id(){
    return student_id;
}


void messenger(){
int id;

   Student newStudent();

   cin>>id;      //this will drop the name and class
   newStudent.set_id(id);
   newStudent.print_id();
return;
}

void main() {
//Student newStudent();
string input="";
bool finished=false;

cout<<PROMPT; // prompt the user
        while(!finished) {
                if(input!="") cout<<PROMPT;
                cin>>input;
                if(input=="enroll") {
                        cout<<PROMPT<<"Enroll student:"<<endl;
                        messenger();
                        //cin>>input;
                        //newStudent.enroll(input );
                }
                else if(input=="drop") {
                        cout<<PROMPT<<"Enter ID:"<<endl;
                }
                else if(input=="roster") {
                        cout<<"This will print formatted list of students"<<endl;
                }
                else if(input=="quit") {
                        finished=true;
                }
        }
}