How select query is generated in a Custom Post Type?

You can use meta_query property when fetching post data using new WP_Query()

$vehicles = new WP_Query([
    'post_type'  => 'vehicle',
    'meta_query' => [
        'relation' => 'AND',
        [
            'key'   => 'wheel',
            'value' => '4',
        ],
        [
            'key'   => 'color',
            'value' => 'blue',
        ]
]);

WP_Query official docs

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)