How to add product to cart

I want to add product from product entity into cart entity, what i have thought is, i retrieve the cart and product list, create a new cart, and change cart's attribute value's into product's attribute value's, and then commit it, my latest progress is i can make the button “add to cart” in product object added to cart, but in the cart page, it still now showing anything, what should i do? Please here are the image of product (animalBreed) and my microflow
1 answers

the relation should be other way around one cart can have multiple products and you need to set that association in product to the cart object you wanna add it to.