The path that the business analyst should take to find information about custom apps, active Salesforce Sites, active flows, custom tabs, and Visualforce pages is to review configuration settings. Configuration settings are options or preferences that can be customized or modified in Setup. They can help the business analyst understand how Salesforce was implemented and what features or components were enabled or disabled.
Custom apps, active Salesforce Sites, active flows, custom tabs, and Visualforce pages are examples of configuration settings that can be accessed or changed in Setup.Conducting stakeholder interviews may be a useful way to gather information about business needs, expectations, or feedback, but not about technical details or configuration settings. Reading business process documentation may be a useful way to understand how a business process works or flows, but not about technical details or configuration settings. References:
https://trailhead.salesforce.com/content/learn/modules/salesforce-business-analyst-certification-prep/customer-di
https://trailhead.salesforce.com/content/learn/modules/salesforce-business-analyst-certification-prep/business-pro

Explanation
The approach that the business analyst should take to begin this process is to schedule a meeting with stakeholders and create a journey map. A journey map is a tool that creates a visualrepresentation of the steps or stages that a user goes through when interacting with a system or solution. A journey map helps to understand and document the user's experience, needs, goals, pain points, emotions, and touchpoints across their entire lifecycle. A journey map also helps to identify any gaps or opportunities for improvement or innovation in the user journey. The business analyst should schedule a meeting with stakeholders and create a journey map by asking questions, collecting feedback, drawing diagrams, and validating information.
Scheduling a meeting with stakeholders and creating a journey map helps to begin this process by engaging and involving them in defining and designing the new client onboarding process.
References:https://trailhead.salesforce.com/content/learn/modules/salesforce-business-analyst-certification-prep/

Explanation
A gap analysis is a document that compares the current state and the desired state of a business process or system, and identifies the gaps or differences between them. It helps to determine what needs to be changed or added to achieve the desired state. A BA should prepare a gap analysis to describe the additional business needs imposed by the new regulatory requirements, and how they affect the existing processes built on Salesforce. References:
https://trailhead.salesforce.com/en/content/learn/modules/business-analysis-gap-analysis/understand-gap-analysi

This answer states that circulating the requirements to stakeholders, incorporating feedback, and obtaining sign-off is what the BA should do to ensure alignment on goals and strategies across NTO's organization for creating an engaging site for its customers using Experience Cloud. Circulating the requirements to stakeholders means that the BA shares the written statements that describe what the solution must do or have to meet the goals and strategies of NTO's organization with the people who have a significant interest or influence in the project outcome. Incorporating feedback means that the BA revises and updates the requirements based on the comments or suggestions from the stakeholders. Obtaining sign-off means that the BA gets a formal approval or confirmation from the stakeholders that they agree with and accept the requirements. References:
https://trailhead.salesforce.com/en/content/learn/modules/salesforce-business-analyst-quick-look/use-user-stories