Kode dari tutorial https://solusipress.com/mengarahkan-isian-forminator-ke-pesan-whatsapp/

functions-3.php

<?php
add_action( 'wp_enqueue_scripts', 'solusipress_jquery_number_wa' );
function solusipress_jquery_number_wa() {
	if( is_page( 'forminator-test-wa' ) ) {
		wp_enqueue_script( 'jquery-number', 'https://businessprofile.solusipress.com/wp-content/uploads/custom-css-js/18.js', array('jquery') );
		wp_enqueue_script( 'input-spinner', 'https://businessprofile.solusipress.com/wp-content/uploads/custom-css-js/105.js', array('jquery') );
		wp_enqueue_script( 'underscore' );
	}
}
add_action( 'wp_footer', 'solusipress_forminator_whatsapp' );
function solusipress_forminator_whatsapp() {
	if( is_page( 'forminator-test-wa' ) ) { ?>
<script type="text/javascript">										
( function($){
    
	wrap_spinner( 'forminator-field-number-1' );
        $( '#calculation-1-field' ).hide();
        $( '#calculation-1-field' ).parent().append( '<div id="total_html" style="font-weight:600;font-size:22px"></div>' );
        set_total();
        $( '#calculation-1-field' ).on( 'change', function(){
            set_total();
        } );				
	
	function wrap_spinner( id ) {
		$( '#'+id ).css( 'display','inline-block' )
				   .css( 'margin-top', '0px' )
				   .css( 'border', '1px solid #ccc' );
		$( '#'+id ).attr( 'step', '1' )
				   .attr( 'readonly', 'readonly' );		
		$( '#'+id ).addClass( 'input-text qty text' );
		$( '#'+id ).wrap( '<div class="quantity buttons_added"></div>' );		
		$( '#'+id ).parent().prepend( '<input type="button" value="-" class="minus">' );
		$( '#'+id ).parent().append( '<input type="button" value="+" class="plus">' );
	}
	
    function set_total() {
        var tot = $('#calculation-1-field').val();
        $( '#total_html' ).html( 'Rp' + $.number( tot, 0, ',', '.' ) );
    }	
	
	/* send to WhatsApp */
	(function(){
		var data = {};
		var valueMap = {};
		
		$( '.forminator-radio input, .forminator-checkbox input' ).each( function(idx, elm) {
			var optionText = $(elm).parent().find( 'span:last-child' );
			valueMap[ $(elm).attr('value') ] = optionText.html();
		} );
		
		$( 'body' ).on( 'before:forminator:form:submit', function( formData ) {					
			$( '.forminator-input--wrap, .forminator-radio, .forminator-checkbox' ).each( function( idx, elm ) {
				var the_input = $(elm).find('input:not([type=button])');
				var label = $(elm).closest( '.forminator-field' ).find( '.forminator-label' ).contents().get(0).nodeValue;
				if( the_input.attr('type') == 'radio' || the_input.attr('type') == 'checkbox' ) {
					if( the_input.prop( 'checked' ) ) {
						var the_val = valueMap[ the_input.prop('value') ];
						if( data[ label ] != undefined && data[ label ] != '' ) {
							data[ label ] += ', ' + the_val;
						} else {
							data[ label ] = the_val;
						}
					}
				} else {
					data[ label ] = the_input.val();
				}
			} );
			data[ 'Total Price' ] = $( '#total_html' ).html();
		} );			
		$( 'body' ).on( 'forminator:form:submit:success', function( formData ) {
			
			var the_text = "";
			_.each( data, function(value, key, list){
				the_text += key + ": " + value + "\n";
			} );

			the_text = window.encodeURIComponent( the_text );
			var the_phone = '6281314997198'; // ganti nomor dengan milik Anda
			var url = 'https://api.whatsapp.com/send?phone=' + the_phone + '&text=' + the_text;
			var isSafari = !!navigator.userAgent.match(/Version\/[\d\.]+.*Safari/);
			var iOS = /iPad|iPhone|iPod/.test(navigator.userAgent) && !window.MSStream;

			if( isSafari && iOS ) {
				location = url;
			} else {
				window.open( url, '_blank' );
			}
			
		} );		
	})();
	
} )( jQuery );	
</script><?php
	}
}