php - Display email column from another table instead of referencing ID in laravel backpack

3 of the tables in my database are:

1. Orders
2. Products
3. User

This is the migration of orders table

public function up()
{
    Schema::create('orders', function (Blueprint $table) {
        $table->id();
        $table->foreignId('user_id')->constrained();  // FK to Users table
        $table->foreignId('product_id')->constrained();  // FK to product table
        // ...
        $table->timestamps();
    });
}

Now when I am Listing all the data in my Admin panel, I want to display:

1. email (which is unique) from user Table instead of user_id
2. product_name (which is also unique) from products Table instead of product_id

app/Http/Controllers/Admin/OrderCrudController.php

[
            'name'  => 'user_id', // Table column which is FK for Customer table
            'label' => 'User', // Label for HTML form field
            'type'  => 'select2',  // HTML element which displaying transactions
            
            'placeholder' => 'Select a User', // placeholder for the select
            'allows_null' => true,
            'attribute' => 'email', // Column which user see in select box
            'minimum_input_length' => 1,
            'hint' => 'The person who ordered the product',
        ],
        [
            'name'  => 'product_id',
            'label' => 'Product',
            'type' => 'select',

            'placeholder' => 'Select a Product', // placeholder for the select
            'allows_null' => true,
            'attribute' => 'name', // Column which user see in select box
            'minimum_input_length' => 1,
            'hint'  => 'The product which was ordered',
        ],
]

When I use the above code in protected function setupCreateOperation(), it gives me the desired results.

in setupListOperation you use Columns

there is no column in Backpack called "select2", in the end, columns are read-only and users can not input data for columns.

to display user's email, you can use select column:

[
   
   'label'     => 'email', // Table column heading
   'type'      => 'select',
   'name'      => 'user_id',
   'key'=>'email' 
   'entity'    => 'user', // the method that defines the relationship in your Model
   'attribute' => 'email', // foreign key attribute that is shown to user
   'model'     => User::class, // foreign key model
],

make sure you have user() relation in your Order model.