我如何用eloquent为laravel 8编写这个查询？

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class User extends Model
{
    protected $table = 'users';
}

<?php

namespace App\Http\Controllers;

use App\Models\User;
use Illuminate\Http\Request;

class UserController extends Controller
{
    public function getUsers()
    {
        // 查询所有用户
        $users = User::all();

        // 查询特定条件的用户
        $users = User::where('age', '>', 18)->get();

        // 查询单个用户
        $user = User::find(1);

        // 创建新用户
        $user = new User;
        $user->name = 'John Doe';
        $user->email = 'john@example.com';
        $user->save();

        // 更新用户
        $user = User::find(1);
        $user->name = 'Jane Doe';
        $user->save();

        // 删除用户
        $user = User::find(1);
        $user->delete();

        return view('users', ['users' => $users]);
    }
}