Sun Country Airlines operates from Terminal 5 at John F. Kennedy International Airport (JFK). Passengers can check in at counters or kiosks and proceed through TSA security. Terminal 5 offers dining, shopping, and comfortable seating, ensuring a convenient travel experience.
https://airportsterminalguides.....com/sun-country-air

Frontier Airlines operates from Terminal N (North Terminal) at Hartsfield–Jackson Atlanta International Airport (ATL) for both arrivals and departures. This terminal provides a variety of services, including check-ins, baggage handling, and other passenger amenities​.
https://airportsterminalguides.....com/frontier-airlin