Add products to 2 categories?

Hi all,

I’m new to magento, and websites in general, for my work I’ve been tasked to clean up our webshop. Now I have multiple categories, one of which is our sale. The products that are in the categorie Sale also have to be in their own category.

I’ve managed to add the products to both categories but when im in the sale tab on the website the products dont link to their own URL. Does anyone know how i can fix this?

I truly hope that my question makes sense.