function wpyog_press_scripts() {
   // Load Google Maps API. Make sure to add the callback and add custom-scripts dependency
   wp_register_script('wpyog-google-maps', 'https://maps.googleapis.com/maps/api/js?key=AIzaSyBDpN1kFL3vTBAjWQySIVsCMdrzDTRdTL0&callback=initMap', array(),
  '1.0',
  true
   );
}
add_action( 'wp_enqueue_scripts', 'wpyog_press_scripts' );

add_shortcode( 'wpyog_map_locator_frontend', 'wpyog_map_locator_frontend' );
function wpyog_map_locator_frontend(){
    global $wpdb,$content;
    ob_start();
    wp_enqueue_script('wpyog-google-maps'); ?>
    <script>
    var map;
    var markers = [];
    var infoWindow;
    var locationSelect;

    function initMap() {
       var uk_country = {lat: 51.509865, lng: -0.118092};
        map = new google.maps.Map(document.getElementById('map'), {
  center: uk_country,
   zoom: 6,
mapTypeId: 'roadmap',
mapTypeControlOptions: {style: google.maps.MapTypeControlStyle.DROPDOWN_MENU}
   });
   infoWindow = new google.maps.InfoWindow();
}

<?php
   $includeFile = WPYog_MAP_LOCATOR_DIR.'views/wpyog_map_locator_frontend.php';
   include( $includeFile );
    return ob_get_clean();
  }

<div id="map" style="width: 100%; height: 90%;"></div>