**YITH Point of Sale for WooCommerce** Hide cash in hand to cashiers

functions.php

<?php 
if ( defined( 'YITH_POS_VERSION' ) && ! function_exists( 'yith_pos_add_user_role_to_pos_class' ) ) {
	add_filter( 'yith_pos_body_classes', 'yith_pos_add_user_role_to_pos_class' );
	function yith_pos_add_user_role_to_pos_class( $body_class ) {

		if ( is_user_logged_in() ) {
			$user       = wp_get_current_user();
			$body_class = array_merge( $body_class, (array) $user->roles );
		}

		return $body_class;
	}

	if ( ! function_exists( 'yith_pos_customization_css' ) ) {
		add_action( 'wp_enqueue_scripts', 'yith_pos_customization_css', 99 );

		function yith_pos_customization_css() {
			$css = ".yith_pos_cashier  .modal-wrap.modal-cash-in-hand,
						.yith_pos_cashier .dropdown .dropdown-menu > div.dropdown-item.manage-cash {
                            display: none;
						}";
			wp_add_inline_style( 'yith-pos-frontend', $css );
		}
	}
}

You don't have a code to hide the buttons, add surcharge or fee and apply coupon from the frontend of this same plugin.