Laravel

// app/Models/Product.php
class Product extends Model
{
    protected $fillable = ['name', 'price'];

    public function scopeAffordable($query) {
        return $query->where('price', '<', 100);
    }
}

// routes/web.php
Route::get('/products', function () {
    return Product::affordable()->latest()->paginate(20);
});

Route::post('/products', function (Request $request) {
    $data = $request->validate([
        'name'  => 'required|string|max:200',
        'price' => 'required|numeric|min:0',
    ]);
    return Product::create($data);
});