Explanation
Two kinds of queries that the methods in Salesforce B2B Commerce services perform by default are SOQL and schema-less queries. SOQL is the query language that is used to retrieve data from Salesforce objects and fields. Schema-less queries are queries that do not specify the object or field names explicitly, but use placeholders instead. For example, ccrz.ccServiceDao.getQuery('SELECT Id FROM Account WHERE Name
= :name') is a schema-less query that uses :name as a placeholder for the field name. The framework will transform this query to use the actual field name based on the query transformation rules. Salesforce References: B2B Commerce and D2C Commerce Developer Guide, Query Transformation

To enable the ability to add new shipping and billing addresses during checkout, a developer should enable Buyer Managed Contact Point Addresses within the Shipping Address standard component in the Checkout subflow. The Buyer Managed Contact Point Addresses is a feature that allows customers to add, edit, or delete their shipping and billing addresses during checkout. The developer can enable this feature by setting the buyerManagedContactPointAddressesEnabled attribute to true in the Shipping Address standard component in the Checkout subflow. The Shipping Address standard component is a component that displays and collects the shipping address information for the cart or order. The Checkout subflow is a subflow that defines the steps and components for the checkout process in the storefront. Creating a new shipping address checkout subflow that utilizes the Buyer Managed Contact Point Addresses component is not a valid way to enable this feature, as there is no such component as Buyer Managed Contact Point Addresses. Enabling Buyer Managed Contact Point Addresses within Commerce Administration is not a valid way either, as this feature is not configurable in Commerce Administration. Creating a Lightning web component that enables this functionality and replaces the current shipping address screen within the Checkout subflow is not a valid way either, as this is unnecessary and complicated when there is already a standard component that supports this feature. Salesforce References: [B2B Commerce Developer Guide: Buyer Managed Contact Point Addresses],
[B2B Commerce Developer Guide: Shipping Address Component], [B2B Commerce Developer Guide:
Checkout Subflow]

To implement a Lightning web component which can read, create and modify single records, the recommended path forward is to use Lightning Data Service. Lightning Data Service is a service that provides access to Salesforce data and metadata, cache management, and data synchronization across components.
Lightning Data Service allows developers to use standard components or base componentsto perform CRUD (create, read, update, delete) operations on single records without writing Apex code or SOQL queries.
Lightning Data Service also handles data caching, performance optimization, and conflict resolution automatically. Using base components is not a sufficient way to implement a Lightning web component which can read, create and modify single records, as base components are only user interface elements that do not provide data access or manipulation functionality by themselves. Base components need to be used with Lightning Data Service or other services to perform CRUD operations on single records. Writing custom functions against a wire adapter is not a recommended way to implement a Lightning web component which can read, create and modify single records, as it involves writing complex and error-prone JavaScript code that may not be efficient or scalable. Writing custom functions against a wire adapter also requires handling data caching, performance optimization, and conflict resolution manually. Creating an Apex controller is not a recommended way either, as it involves writing Apex code that may not be necessary or optimal for performing CRUD operations on single records. Creating an Apex controller also requires exposing Apex methods using @AuraEnabled or @RemoteAction annotations and invoking them from JavaScript code using imperative calls or promises. Salesforce References: Lightning Web Components Developer Guide: Access Salesforce Data, Lightning Web Components Developer Guide: Base Components, [Lightning Web Components Developer Guide: Call Apex Methods]

The event that should be triggered when user facing info, warning or error messages need to be displayed on a Visualforce page is pageMessage. This event is triggered by the displayPageMessage method of the CCRZ.util class, which is a utility class that provides various helper methods for common tasks. The event can be used to display a message on the page with a specified type, title, and text. For example, CCRZ.util.displayPageMessage('error', 'Oops!', 'Something went wrong.') will trigger the pageMessage event and display an error message on the page. Salesforce References: B2B Commerce and D2C Commerce Developer Guide, Events, Util Class

Useful debugging information in Salesforce B2B Commerce implementation can be garnered in three ways:
Enabling the logging token via Admin and subsequently inspecting the logs via the browser console. This will enable logging messages and errors to the browser console, which can be viewed by opening the Developer Tools in the browser. The logging token can be enabled by setting the value of CO.logToken to true in CCAdmin.
Enabling debugging options for the current user and visually inspecting the Salesforce debug logs. This will enable logging messages and errors to the Salesforce debug logs, which can be viewed by opening the Debug Logs page in Salesforce Setup. The debugging options can be enabled by creating a Debug Level and a Trace Flag for the current user in Salesforce Setup.
Logging into the community as a system administrator to identify any potential permissions or Visualforce exceptions. This will allow viewing any errors or warnings that may occur on the community pages due to insufficient permissions or Visualforce issues. The system administrator can also access CCAdmin and other tools from within the community. Salesforce Reference: B2B Commerce and D2C Commerce Developer Guide, Logging, Debug Your Code