How to use Ajax in any form submission?

<script type="text/javascript">

    $(document).ready(function() {

       $("FORMIDORCLASS").submit(function(e){

            // FORMIDORCLASS will your your form CLASS ot ID

            e.preventDefault();

       $.ajaxSetup({

            headers: {

                 'X-CSRF-TOKEN': $('meta[name="_token"]').attr('content')

                // you have to pass in between tag

            }

    })

     var formData = $("FORMIDORCLASS").serialize();

    $.ajax({

          type: "POST",

         url: "",

         data : formData,

         success: function( response ) {

              // Write here your sucees message

         }, error: function(response) {

            // Write here your error message

         },

    });

    return false;

   });

});

</script>