Step 1:

Open your themes functions.php file

You can find this file by going to your installation folder and navigating to ROOT/wp-content/themes/THEME_NAME or THEME_NAME-child or from the Dashboard > Appearance > Theme Editor.

Step 2:

Now add following code to the file at the bottom

add_action(‘woocommerce_before_cart_contents’, ‘cart_shipping_notice’);

function cart_shipping_notice( ) {
echo ‘<div class=”cart_shipping_notice”><h3 style=”font-size: 16px;color: #ff0000;”>Please allow 1 Business day for the order to process before the order is shipped out.</h3>
</div>’; }

or

function cart_shipping_notice( ) {
echo ‘<p class=”allow”><strong>Special Shipping Notice: Orders are shipped within 1 business day of receipt. However, due to the current pandemic, some deliveries are taking longer than expected. SprayLabs cannot guarantee delivery times.</strong></p>’;

NOTE: To change the Checkout page:

add_action( ‘woocommerce_before_checkout_form’, ‘checkout_shipping_notice’);

function checkout_shipping_notice( ) {
echo ‘script or text goes here’; (See above #2 for examples of script/text)
}