i want to show just one category listing

I don't understand your question. Please post screenshots and/or explain more what you want to do.

So you want to display a listing of products of a category ? You can do so by creating a menu of type hikashop product listing. Then, you need to go in the hikashop options of the menu to set the "parent category" option to the category from which you want to display the products.

You can follow that tutorial: www.hikashop.com/support/documentation/6...d.html#products_menu

Could you give a link to an example with joomla because I still don't understand ?

One category list is called "products listing" because you are actually listing all the products of one category for a menu. That's what I explained earlier. But you said that it's not that.... So I'm kind of lost

Once you choose products listing, you need to enter the name of your menu and click on the button "apply". That will create your menu. Then, on the right, click on the "hikashop options" link to go to the hikashop options of that menu. There, you need to set the category from which you want to display the products in the option "parent category" and save.

In type of content, you should have product.
How come you don't have the option "parent category" ?
If you login on our demo backend website and then use the URL demomain.hikashop.com/administrator/inde...=menus&task=edit&cid []=58 you will see the option "parent category" on the left. You should have the same option on your end.