How do I access dynamically created objects and their properties in JavaScript?

If I write a function that creates a new person and attach it to an onClick event on a button, how can I access the data that was entered without a variable name?

When a user presses the button, the user can enter values when prompts come up, but nothing prints to the console upon completion?

What I tried - I tried the followng code:

     <button type="submit" onClick="addNewPerson()">Add New Person</button>

     class Person {
       constructor(fname, lname, birthDate) {
         this.firstName = fname;
         this.lastName = lname;
         this.dov = birthDate;
       }
     }

     let person1 = new Person("Mark", "Johnson", "12-07-1972");
     let person2 = new Person("John", "Miller", "08-017-1923");

     function addNewPerson() {
       let ffname = prompt("enter your firstname", "Roger");
       let llname = prompt("enter your lastname", "Doger");
       let ddov = prompt("enter your date of birth", "July 6 2024");

       return new Person(ffname, llname, ddov);
     }

      console.log(addNewPerson())
      console.log(person1); 
      console.log(person2); 
      console.log(new Person(this.fname, this.lname, this.birthDate));

What I was expecting - When the button is clicked, the values entered into the prompts would be displayed in the console. It does not. This code only prints the following to the console:

    Object { firstName: "Roger", lastName: "Doger", dov: "July 6 2024" }
    Object { firstName: "Mark", lastName: "Johnson", dov: "12-07-1972" }
    Object { firstName: "John", lastName: "Miller", dov: "08-017-1923" }
    Object { firstName: undefined, lastName: undefined, dov: undefined }

The dynamically created person objects are not being stored or referenced properly outside the"addNewPerson" function

A different approach is to store dynamically created persons in an array

class Person {
      constructor(fname, lname, birthDate) {
        this.firstName = fname;
        this.lastName = lname;
        this.dov = birthDate;
      }
    }

    let persons = [];

    let person1 = new Person("Mark", "Johnson", "12-07-1972");
    let person2 = new Person("John", "Miller", "08-17-1923");

    persons.push(person1);
    persons.push(person2);

    function addNewPerson() {
      let ffname = prompt("Enter your firstname", "Roger");
      let llname = prompt("Enter your lastname", "Doger");
      let ddov = prompt("Enter your date of birth", "July 6 2024");

      let newPerson = new Person(ffname, llname, ddov);
      persons.push(newPerson);

      console.log(newPerson); 
    }
console.log(persons); 
console.log(person1); 
console.log(person2);