It is possible to get a cheap flight by showing up at the airport, but it's not guaranteed. There are some airlines that offer last-minute deals for unsold seats, but the availability of these deals depends on several factors, such as the destination, the time of year, and the number of unsold seats.
If you decide to show up at the airport to try to get a cheap flight, it's important to keep in mind that there may not be any available seats on the flight you want to take, or the available seats may not be at a discounted price. Additionally, buying a ticket at the airport may come with extra fees, such as a convenience fee or a fee for booking over the phone.
In general, it's always best to plan and book your flight in advance to ensure the best deal. If you do decide to try your luck at the airport, make sure to arrive early and be prepared to pay extra fees if necessary. It's also a good idea to have a backup plan in case you are unable to find a cheap flight.