How do I load a CSS style into WordPress admin area only?

I’m trying to load a CSS file for my WordPress post area, but having no luck. I have read over the wp_enqueue_style function and came up with the code below, but it doesn’t load up. Is there a tag or character missing from my code. I have a custom write panel when a user post that I want to style with the CSS file. Any help would be great.

How to get dynamically custom post type that are under a certain category

I have a custom post type for a theme I’m developing that is named products where I will save a catalogue of products. I want to categorize these products, I’ve added the taxonomy category to the post type and I will create the categories needed to assign each post to the correct one. I’m not very informed about wordpress functions, I want to ask how I can get my custom post type that are assigned to each category. I’m thinking to do multiple WP_Query() but I don’t think this will be a good idea for performances. Is there another way? The solution I want to implement is using ajax with vue.js with the REST API to have a category list that when clicked will load the relative posts and the category name, description. Any hepl?