Use official guidance to identify the questions your project needs to answer. Applicability depends on the service and organisation; a working website does not by itself demonstrate legal compliance.
Accessibility
GOV.UK accessibility guidance explains the public-sector context. Ask who will test your actual journeys, how defects are prioritised and who maintains any statement.
Cookies and notices
ICO privacy notices and cookies is a starting point for information-handling questions. Inventory the technologies used before asking for a banner or policy.
GOV.UK cookie guidance offers technical considerations. Your adviser should assess the current rules for the proposed measurement tools and purposes.