gift product module

i want add some to products a gift product
how can i add?

Can't you just say that the free product will be included with the product in the description of the product ?

yes but not for itself with a product

So you want that when a user adds a product, a second product is automatically added to the cart ?
That would require a code customization of one of the checkout views.
It can't just be done with the options in HikaShop.