<human>:  How to book a flight?
<bot>: To book a flight, you will need to first decide on the destination, travel dates, and flight class that fits your needs. You can then search online or use a travel agent to compare prices and find the best deal. Once you have found the right flight, you can book directly online or call the airline to book the flight over the phone. Make sure to double check all the details before completing the booking, including the flight times, number of passengers, and any applicable fees.