Check out example codes for "ionic alert". It will help you in understanding the concepts better.

Code Example 1

import { Component } from '@angular/core';
import { AlertController } from '@ionic/angular';

@Component({
  selector: 'alert-example',
  templateUrl: 'alert-example.html',
  styleUrls: ['./alert-example.css'],
})
export class AlertExample {

  constructor(public alertController: AlertController) {}

  async presentAlertConfirm() {
    const alert = await this.alertController.create({
      header: 'Confirm!',
      message: 'Message <strong>text</strong>!!!',
      buttons: [
        {
          text: 'Cancel',
          role: 'cancel',
          cssClass: 'secondary',
          handler: (blah) => {
            console.log('Confirm Cancel: blah');
          }
        }, {
          text: 'Okay',
          handler: () => {
            console.log('Confirm Okay');
          }
        }
      ]
    });

    await alert.present();
  }

}

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