Why won’t my Custom CSS Load

hey please include style sheet like this

<?php

add_action( 'wp_enqueue_scripts', 'enqueue_parent_theme_style' );
    function enqueue_parent_theme_style() {
    wp_enqueue_style( 'parent-style', get_stylesheet_uri() );
}

and also stylesheet not require to load jQuery so please change your code to like this

if ( ! function_exists( 'add_additional_css' ) ) {
function add_additional_css() {
    wp_enqueue_style( 'webmarket-child', get_stylesheet_uri() , array( 'main' ) );
    wp_register_style( 'slick', get_stylesheet_directory_uri() . '/slick/slick.css');
    wp_enqueue_style('slick');
}
add_action( 'wp_enqueue_scripts', 'add_additional_css', 20 ) 

I think it will work fine.