Cookie management via JS?

Question

JavaScript

The question is a little deeper than the title.

We are making a website and, according to European laws, we need to manage cookies.
An example like a Mercedes The


question is how to track the appearance of new cookies?
What would then check whether the user has.
Manually or somehow automatic is checked?
Because there are several "categories" , technical, marketing and analytics.
And they have more subcategories.