What do you do first when you arrive at the airport?

the part of the plane where the captain and co-pilot sit to fly the plane

when the passengers get on the plane

It is the area of entry into a Country, typically at the airport at which goods and cargo are searched for various reasons, such as ensuring persons are bringing in no illegal items etc

The document you need to travel to different countries

Bags that are small enough to take on the plane with you

the place where passengers pick up their bags after the plane lands

It is the area where passengers board to the aircraft

It is the code written on your boarding pass.

What types of seats are available on a plane?

more expensive tickets with better seating and more services; first-class has bigger seats than economy or coach class

to leave the ground, usually in a plane