where can I get springboard ai curricullum reddit code example

Example 1: How do I get a YouTube video thumbnail from the YouTube API?

$data = file_get_contents("https://www.googleapis.com/youtube/v3/videos?key=YOUR_API_KEY&part=snippet&id=T0Jqdjbed40");
$json = json_decode($data);
var_dump($json->items[0]->snippet->thumbnails);

Example 2: when should I use a DIRECTORY_SEPARATOR vs a slash

It doesn't matter -- PHP's IO functions will internally convert 
slashes to the appropriate character.