try this and perhaps you can read on to show columns syntax and mysql_query function
<?php
$db = mysql_connect("database_host", "user");
mysql_select_db("Database_name");
$result = mysql_query("SHOW COLUMNS FROM TableName");
$cbo_field_names = "";
while (list($field_name) = mysql_fetch_row($result)) {
$cbo_field_names .= "<option>$field_name</option>";
}
?>
just echo the $ret variable between select tags just like
<select><?=$cbo_field_names?></select>