Find all product ID from array of customfield

$product = array(
    'post_type' => 'product',
    'post_status' => 'publish',
    'posts_per_page' => -1,
    'meta_query' => array(
        array(
            'key' => 'product_cip',
            'value' => 'some value',
            'compare' => '=',
        )
    ),
    'fields' => 'ids',
);


$product_post = get_posts($product);
echo count($product_post);

if you have get all products data

$products_array = array();
foreach ($product_post as $v){
    $_product = wc_get_product($v);
    echo $_product->get_name().',';
    $products_array[] = $_product;
}