Example code for Geo location Meta fields

Here you are:

<?php
add_filter( 'rwmb_meta_boxes', function( $meta_boxes ) {
    $meta_boxes[] = [
        'title' => 'Test',
        'geo' => [
            'api_key' => 'your_api_key',
        ],
        'fields' => [
            [
                'id' => 'address',
                'type' => 'text',
                'name' => 'Address',
            ],
            [
                'id' => 'administrative_area_level_1',
                'type' => 'text',
                'name' => 'State',
            ],
            [
                'id' => 'country',
                'type' => 'text',
                'name' => 'Country',
            ],
        ],
    ];
    return $meta_boxes;
} );