我是新手


<?php
namespace app\index\controller;
use thinkphp\Controller;
use think\Db;
class Index
{
public function index()
{

//print_r($_GET);



$data=Db::name('user')->find();
// print_r($data);

$this->assign('UserName',$Name);

//print_r($Name);


return $this->fecth();

}
}

问题1：致命错误: Call to undefined method app\index\controller\Index:: fetch()

问题2：
return $this->fecth();
提示
致命错误: Call to undefined method app\index\controller\Index::assign()

请高手指点，谢谢