Code:
#include<iostream>
#include<string>
using namespace std;


class Human
{
    public:
        string name;
        int age;
        
        void IntroduceSelf()
        {
            cout << "I am " + name << " and am ";
            cout << age << " years old" << endl;
        }
};


int main()
{
    Human firstMan;
    firstMan.name = "Adam";
    firstMan.age = 30;
    
    Human firstWoman;
    firstWoman.name = "Eve";
    firstWoman.age = 28;
    
    firstMan.IntroduceSelf();
    firstWoman.IntroduceSelf();
}
Code:
 error: ‘Human’ was not declared in this scope; did you mean ‘human’?   20 |         Human firstMan;
      |         ^~~~~
      |         human
sams.cpp:21:9: error: ‘firstMan’ was not declared in this scope
   21 |         firstMan.name = "Adam";
      |         ^~~~~~~~
sams.cpp:24:14: error: expected ‘;’ before ‘firstWoman’
   24 |         Human firstWoman;
      |              ^~~~~~~~~~~
      |              ;
sams.cpp:25:9: error: ‘firstWoman’ was not declared in this scope
   25 |         firstWoman.name = "Eve";
      |         ^~~~~~~~~~