How to get callback on selecting each option in ion select (angular)

ionic verison : 6.12.3

<ion-select (ionChange)="onChange($event,item,'a')"> 
          <ion-select-option value="f" >Female</ion-select-option>
          <ion-select-option value="m" >male</ion-select-option>

how to get callback on selecting each option

The $event supplies the value under .detail.value. Alternatively you yan use [(ngModel)] together with (ngModelChange)

I need callbaack after just clicking option itself

Please back up and explain your ultimate goal, such as “I have a questionnaire that needs to present different questions depending on the gender of the respondent. How can I make the contents of my form change depending on the current value of a particular control?”.

Try to avoid fixating on how you think this should be done technically, because you are going to get pushback on the term “callback” - the RxJS library that is one of the most fundamental building blocks of Angular was arguably invented with the goal of banishing the word “callback” from the lexicon of web developers.