get_userdata by username

get_userdata() function is an alias of get_user_by('ID') function. Use this code:

$username="your user name";
$user = get_user_by('login', $username);

It will return WP_User object on success, or false on failure. See Codex.

REST API: http://example.com/wp-json/wp/v2/users/<id>

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