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

Code Example 1

<!-- Default Checkbox -->
<ion-checkbox></ion-checkbox>

<!-- Disabled Checkbox -->
<ion-checkbox disabled="true"></ion-checkbox>

<!-- Checked Checkbox -->
<ion-checkbox checked="true"></ion-checkbox>

<!-- Checkbox Colors -->
<ion-checkbox color="primary"></ion-checkbox>
<ion-checkbox color="secondary"></ion-checkbox>
<ion-checkbox color="danger"></ion-checkbox>
<ion-checkbox color="light"></ion-checkbox>
<ion-checkbox color="dark"></ion-checkbox>

<!-- Checkboxes in a List -->
<ion-list>
  <ion-item *ngFor="let entry of form">
    <ion-label>{{entry.val}}</ion-label>
    <ion-checkbox slot="end" [(ngModel)]="entry.isChecked"></ion-checkbox>
  </ion-item>
</ion-list>

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

@Component({
  selector: 'app-page-home',
  templateUrl: 'home.page.html',
  styleUrls: ['home.page.scss']
})
export class HomePage {
  public form = [
      { val: 'Pepperoni', isChecked: true },
      { val: 'Sausage', isChecked: false },
      { val: 'Mushroom', isChecked: false }
    ];
}

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