There is no functionality provide WooCommerce to retrieve last category page viewed. But, I solved.

First create a custom action, check if page is category page, and set Cat ID to session data if so. Then on your button, use this to get proper URL.

add_action( 'init', 'wp_check_product_cat_sess');
function wp_check_product_cat_sess(){
    if(!session_id()){
        session_start();
    }
}
add_action( 'wp', 'check_product_cats');
function check_product_cats(){
    global $wp_query;
    if( is_product_category() ){
        $_SESSION['set_last_cat_id'] = $wp_query->get_queried_object()->term_id;
    }
    if( is_product() ){
        $get_cats = get_the_terms( $wp_query->get_queried_object(), 'product_cat' ) ;
        if( count( $get_cats ) > 0 ){
            foreach($get_cats as $one_cat ){
                    $_SESSION['set_last_cat_id'] = $one_cat->term_id;
            }
        }
    }  
    if( is_cart()){
        //var_dump( $_SESSION['set_last_cat_id'] );
    }
}
add_filter( 'woocommerce_continue_shopping_redirect', 'woo_add_continue_shop_btn_to_cart', 20 );
function woo_add_continue_shop_btn_to_cart($return_to){
    if( isset( $_SESSION['set_last_cat_id'] ) ){
        $redirect_page_url = get_term_link( $_SESSION['set_last_cat_id'], 'product_cat' );
    }else{
        $redirect_page_url = get_permalink( wc_get_page_id( 'shop' ) );
    }
    return $redirect_page_url;
}

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Let me know your thoughts and questions in the comments.
Email: vyasankit2008@gmail.com

<?php
//add custom fields to WooCommerce products Single Page, Cart Page, Checkout Page, Order Detaile And Save To Database Table Name "wp_woocommerce_order_itemmeta"

add_action( 'woocommerce_before_add_to_cart_button', 'add_fields_before_add_to_cart' );
function add_fields_before_add_to_cart(){ ?>
    <table>
        <tr>
            <td>
                <?php _e( "Name:", "aoim"); ?>
            </td>
            <td>
                <input type = "text" name = "customer_name" id = "customer_name" placeholder = "Name on Gift Card">
            </td>
        </tr>
        <tr>
            <td>
                <?php _e( "Gift Price:", "aoim"); ?>
            </td>
            <td>
                <input type = "text" name = "custom_price" id = "custom_price" placeholder = "Your GiftPrice on Gift Card">
            </td>
        </tr>
    </table>
    <?php
}

/**
 * Add data to cart item
 */
add_filter( 'woocommerce_add_cart_item_data', 'add_cart_item_data', 25, 2 );
function add_cart_item_data( $cart_item_meta, $product_id ) {
    if ( isset( $_POST ['customer_name'] ) && isset( $_POST ['custom_price'] ) ) {
      
        $product = wc_get_product($product_id);      
        $price = $product->get_regular_price();
      
        $custom_data  = array() ;
        $custom_data [ 'customer_name' ]    = isset( $_POST ['customer_name'] ) ?  sanitize_text_field ( $_POST ['customer_name'] ) : "" ;
        $custom_data [ 'custom_price' ] = isset( $_POST ['custom_price'] ) ? sanitize_text_field ( $_POST ['custom_price'] ): "" ;
      
        $custom_data['totalPrice'] = $price + $custom_data [ 'custom_price' ];              
      
        $cart_item_meta ['custom_data']     = $custom_data ;
    }  
    return $cart_item_meta;
}

/**
 * Display custom data on cart and checkout page.
 */
add_filter( 'woocommerce_get_item_data', 'get_item_data' , 25, 2 );
function get_item_data ( $other_data, $cart_item ) {
    if ( isset( $cart_item [ 'custom_data' ] ) ) {
        $custom_data  = $cart_item [ 'custom_data' ];          
        $other_data[] = array( 'name' => 'Name', 'display'  => $custom_data['customer_name'] );
        $other_data[] = array( 'name' => 'GiftPrice', 'display'  => $custom_data['custom_price'] );
    }
    return $other_data;
}

// Set the new calculated price replacing cart item price
add_action( 'woocommerce_before_calculate_totals', 'set_cart_item_calculated_price', 20, 1 );
function set_cart_item_calculated_price( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) ) return;
  
    // Loop through cart items
    foreach ( $cart->get_cart() as $key=>$value ){                      
        if( ! isset( $value['custom_data']['totalPrice'] ) ){ continue; }
      
        if( $value['custom_data']['totalPrice'] > 0 ){
            $value['data']->set_price((float)$value['custom_data']['totalPrice']);
        }
    }
}

/**
 * Add order item meta.
*/
add_action( 'woocommerce_add_order_item_meta', 'add_order_item_meta' , 10, 2);
function add_order_item_meta ( $item_id, $values ) {
    if ( isset( $values [ 'custom_data' ] ) ) {
        $custom_data  = $values [ 'custom_data' ];
        wc_add_order_item_meta( $item_id, 'Name', $custom_data['customer_name'] );
        wc_add_order_item_meta( $item_id, 'GiftPrice', $custom_data['custom_price'] );
    }
}