how to apply exposed filter without apply button in Drupal 8 views?
Try this It may solve your problem. It may not be the proper solution but it will help you apply filter without having to click on apply button.

(function($) {
  $(document).ready(function() {
 $(document).ajaxComplete(function(event, xhr, settings) {
 $(".views-exposed-form .form-select").change(
         function(){
           $(".form-submit").click();
         }
);
  });
       });
})(jQuery);