UpdateCaseQueuable.apxc

public class UpdateCaseQueuable implements Queueable {
    public List<Case> caseList ; 
    public UpdateCaseQueuable(List<Case> cases){
        this.caseList = cases ;  
    }
    
    public void execute(QueueableContext context) {
        for(Case a :caseList){
            a.Description ='Updated from UpdateCaseQueuable';
            a.Status='Closed';
         }
        update caseList;
        
        //Finalizer class 
        SendEmailFinalizer emailFinalizer = new SendEmailFinalizer();
        System.attachFinalizer(emailFinalizer);
    }
}