// Woocommerce - Single product page notification
add_action( 'woocommerce_share', 'custom_cart_notice' );

// Woocommerce - cart page notification
add_action( 'woocommerce_before_cart_table', 'custom_cart_notice' );

// Kadence - side cart notificatin
add_action( 'kadence-after-side-cart', 'custom_cart_notice' );

function custom_cart_notice() {
	$min_amount = 50; //change this to your free shipping threshold

	$current = WC()->cart->subtotal;

	if ( $current < $min_amount ) {
		$added_text = '<div class="woocommerce-message">Buy  ' . wc_price( $min_amount - $current ) . ' worth products more to get free shipping<br/>';
		$return_to = wc_get_page_permalink( 'shop' );
		$notice = sprintf( '%s<a href="%s">%s</a>', $added_text, esc_url( $return_to ), 'Continue shopping</div>' );
		echo $notice;
	}
}