Check if the product is in the cart on different pages [closed]

[Casey]

I have a product page where it shows a list of products and another page with your details and through these two pages I need to check if the product is already in cart.But when I add a product to cart on a given page normally it includes, the problem is when I try to add the same product on another page, it is showing up in the cart with duplicate names being sure that the issue was a warning that the item already in the cart and provide only the accretion or reducing the quantity.I use v3.0.Any help is welcome.Thanks in advance!