Laravel display data from one database table by using the id of that row

So I have a table pages, that looks like this:

public function up()
    {
        Schema::create('pages', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('user_id')->unsigned();
            $table->string('name');
            $table->integer('category')->unsigned();
]        });

        Schema::table('pages', function($table) {
            $table->foreign('user_id')->references('id')->on('core_users')
                ->onUpdate('cascade')->onDelete('cascade');
            $table->foreign('category')->references('id')->on('ecommerce_payment_pages_categories')
                ->onUpdate('cascade')->onDelete('set null');

        });
    }


    public function down()
    {
        Schema::drop('pages');
    }

And a table categories looking like this:

public function up()
    {
        Schema::create('ecommerce_payment_pages_categories', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('user_id')->unsigned();
            $table->foreign('user_id')->references('id')->on('core_users')
                ->onUpdate('cascade')->onDelete('cascade');
            $table->string('name');
            $table->timestamps();
        });
    }

    public function down()
    {
        Schema::drop('categories');
    }

The pages model looks like this:

class Pages extends Model
{

    protected $table = 'pages';


    public function user() {
        return $this->belongsTo("\App\User");
    }

    protected $fillable = [

    ];

    protected $casts = [

    ];

    public function categories() {
        return $this->belongsTo("\App\Models\Categories");
    }
}

And the categories model looks like this:

class PaymentPagesCategories extends Model
{
    protected $table = 'categories';

    public function user() {
        return $this->belongsTo("\App\User");
    }

    protected $fillable = [

    ];

    protected $casts = [

    ];

    public function pages_categories() {
        return $this->hasMany("\App\Models\\Pages");
    }
}

So in my pages table I save in the column category the id of the category that the user selects from a dynamic select that echoes the category id as value and category names as options. But I cannot save it as simple string because in another menu the user has the option to delete categories, so I want that when a category gets deleted to get deleted from the category column in the page table as well. Right now I display the data from the database like this:

public function getGet()
{
    return response()->json(['success' => true, 'payment_pages' => \Auth::user()->payment_pages()->orderBy('id', 'ASC')->get()]);
}

So for the currently authenticated user I display all the data from the page database table.

via Chebli Mohamed