Modify the “Add to Cart” button text for simple and variable products:

/**
 * Modify the "Add to Cart" button text for Simple and Variable Products.
 *
 * This snippet customizes the text on the "Add to Cart" button for
 * both the shop/archive page and single product pages.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */

// Change "Add to Cart" text on shop/archive page
add_filter( 'woocommerce_product_add_to_cart_text', 'custom_add_to_cart_text_archive', 10, 1 );
function custom_add_to_cart_text_archive( $text ) {
    return __( 'Your Custom Text', 'woocommerce' );
}

// Change "Add to Cart" text on single product page
add_filter( 'woocommerce_product_single_add_to_cart_text', 'custom_add_to_cart_text', 10, 1 );
function custom_add_to_cart_text( $text ) {
    return __( 'Your Custom Text', 'woocommerce' );
}

Automatically redirect customers to the checkout page as soon as they add an item to their cart:

 /**
 * Disable AJAX Add to Cart on the Shop page
 *
 * This snippet lets you disable AJAX Add to Cart on the Shop page.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */
add_action( 'wp_enqueue_scripts', 'disable_ajax_add_to_cart_on_shop' );
function disable_ajax_add_to_cart_on_shop() {
    if (is_shop() || is_product_category()) {
        wp_dequeue_script( 'wc-add-to-cart' );
    }
}

// Redirect to checkout after adding to cart
add_filter( 'woocommerce_add_to_cart_redirect', 'custom_add_to_cart_redirect' );
function custom_add_to_cart_redirect() {
    return wc_get_checkout_url();
}

Remove the “Related Products” section from product pages:

 /**
 * Remove Related Products from Product Pages
 *
 * This snippet allows you to remove the "Related Products: from all product pages.
 * This snippet is not compatible with the WooCommerce Checkout Block.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */
remove_action( 'woocommerce_after_single_product_summary', 'woocommerce_output_related_products', 20 );

Enforces a minimum order amount for checkout:

 /**
 * Set Minimum Order Amount for Checkout
 *
 * This snippet allows you to enforce a minimum order amount in order to check out.
 * This snippet is not compatible with the WooCommerce Checkout Block.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */
add_action( 'woocommerce_checkout_process', 'custom_minimum_order_amount' );
add_action( 'woocommerce_before_cart' , 'custom_minimum_order_amount' );
function custom_minimum_order_amount() {
    $minimum = 200; // Set minimum amount
    if ( WC()->cart->total < $minimum ) {
        if( is_cart() ) {
            wc_print_notice( 
                sprintf( 'Your current order total is %s — you must have an order with a minimum of %s to proceed to checkout.', 
                    wc_price( WC()->cart->total ), 
                    wc_price( $minimum )
                ), 'error' 
            );
        } else {
            wc_add_notice( 
                sprintf( 'Your current order total is %s — you must have an order with a minimum of %s to proceed to checkout.', 
                    wc_price( WC()->cart->total ), 
                    wc_price( $minimum )
                ), 'error' 
            );
        }
    }
}

Automatically apply a specific coupon to the cart:

 /**
 * Automatically Apply a Coupon on Checkout
 *
 * This snippet allows you to automatically apply a coupon on checkout. 
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */
add_action( 'woocommerce_before_cart', 'apply_coupon_automatically' );
add_action( 'woocommerce_before_checkout_form', 'apply_coupon_automatically' );

function apply_coupon_automatically() {
    $coupon_code = 'test'; // Replace with the actual coupon code you want to apply.

    // Check if the cart does not already have the coupon applied
    if ( ! WC()->cart->has_discount( $coupon_code ) ) {
        WC()->cart->apply_coupon( $coupon_code );
        wc_print_notices();
    }
}

Add a custom fee to the WooCommerce checkout, for example, a handling fee or packaging fee:

 /**
 * Add a Custom Fee to Checkout
 *
 * This snippet lets you add a custom fee to checkout. For example, a handling fee or  
 * a packaging fee.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */
add_action( 'woocommerce_cart_calculate_fees', 'add_custom_checkout_fee' );
function add_custom_checkout_fee() {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;
    
    WC()->cart->add_fee( 'Handling Fee', 5 );
}

You can hide product prices for visitors who are not logged in:

 /**
 * Hide Prices for Logged-Out Users
 *
 * This snippet lets you hide product prices for logged-out users.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */
add_action( 'wp', 'hide_prices_for_logged_out_users' );
function hide_prices_for_logged_out_users() {
    if ( ! is_user_logged_in() && ! is_admin() ) {
        remove_action( 'woocommerce_single_product_summary', 'woocommerce_template_single_price', 10 );
        remove_action( 'woocommerce_after_shop_loop_item_title', 'woocommerce_template_loop_price', 10 );
    }
}

Show a custom message on the Cart page when the customer qualifies for free shipping:

/**
 * Display a Free Shipping Notice
 *
 * This snippet lets you to display a free shipping notice.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */
add_action( 'woocommerce_before_cart', 'custom_free_shipping_notice' );
function custom_free_shipping_notice() {
    $min_amount = 50; // Set minimum amount for free shipping
    $current_total = WC()->cart->subtotal;
    
    if ( $current_total >= $min_amount ) {
        echo '<div class="woocommerce-info">Congrats! You qualify for free shipping.</div>';
    }
}

Modify the Reviews display name to “F.Lastname”:

/**
 * Modify WooCommerce Product Review Author Format
 *
 * This snippet changes the display of product review authors 
 * to "F. Lastname" format instead of showing their full name.
 *
 * Usage: Add this to your theme's functions.php or a custom plugin.
 */

add_filter('get_comment_author', 'comments_filter_uprise', 10, 1);

function comments_filter_uprise( $author ) {
    $comment = get_comment(); // Retrieve the comment object

    if ( $comment ) {
        // Try getting user by email
        $user = get_user_by('email', $comment->comment_author_email);

        if ( $user ) {
            // Format the author name as "F. Lastname"
            return substr($user->first_name, 0, 1) . '. ' . $user->last_name;
        }

        // If no user found, try by user ID (in case it's a registered user)
        if ( $comment->user_id ) {
            $user = get_userdata($comment->user_id);
            if ( $user ) {
                return substr($user->first_name, 0, 1) . '. ' . $user->last_name;
            }
        }
    }

    // Default: return the original comment author
    return $author;
}