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

Code Example 1

<ion-list>
  <ion-list-header>
    <ion-label>
      Single Selection
    </ion-label>
  </ion-list-header>

  <ion-item>
    <ion-label>Gender</ion-label>
    <ion-select placeholder="Select One">
      <ion-select-option value="f">Female</ion-select-option>
      <ion-select-option value="m">Male</ion-select-option>
    </ion-select>
  </ion-item>

  <ion-item>
    <ion-label>Hair Color</ion-label>
    <ion-select value="brown" okText="Okay" cancelText="Dismiss">
      <ion-select-option value="brown">Brown</ion-select-option>
      <ion-select-option value="blonde">Blonde</ion-select-option>
      <ion-select-option value="black">Black</ion-select-option>
      <ion-select-option value="red">Red</ion-select-option>
    </ion-select>
  </ion-item>

</ion-list>

Code Example 2

<ion-select >
          <ion-select-option *ngFor="let country of countries" value="{{ country.name }}">
            {{ country.name }}
          </ion-select-option>
     </ion-select>

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