Ticket Agents work on airport counters or other designated sales points that airlines might have. In general terms, Ticket Agents greet and help customers and passengers with their flight reservations.
The ground staff is responsible for: Manning the check-in counters that serve departing passengers. ... Assisting passengers by answering questions, providing directions, or attending to their other needs.
Cabin Crew responsibilities include: Understanding the duties of your assigned position during flight and acting your best. Ensuring the satisfaction of passengers by answering questions and offering them assistance.