Check out example codes for "how to extend ts class". It will help you in understanding the concepts better.

Code Example 1

class Info {
  private name: string ;
  constructor(n:string){
    this.name = n ;
  };
  describe(){
    console.log(`Your name is  ${this.name}`);
  }
}

const a = new Info('joyous');
a.describe();

Code Example 2

class Animal {
  move(distanceInMeters: number = 0) {
    console.log(`Animal moved ${distanceInMeters}m.`);
  }
}

class Dog extends Animal {
  bark() {
    console.log("Woof! Woof!");
  }
}

const dog = new Dog();
dog.bark();
dog.move(10);
dog.bark();Try

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