After a plane lands it moves to the apron or the parking area by the power of its engines, then it drops off passengers and cargoes.
The staff prepare for the next take-off.
There are staff who unload cargoes, staff who fill up the airplane with fuel, staff who clean the inside of the plane, and staff who prepare tea and meals. They all work hard to get the plane ready.

Before take-off, there is an inspection to make sure there are no problems with the plane. Specially trained mechanics go into the cockpit and do a careful inspection.
When the inspection is finished passengers get on the plane and cargo is loaded. The cargo is carried out to the plane by its own trailer, and is loaded by a lift for cargo.
When preparations have been made for take-off, the pilot contacts the control tower and asks for permission to take off. Because planes cannot move backwards, sometimes a special tow car pulls the plane into place.

When a plane flies more than a certain amount of time or has some problems, it is put into the hangar to be inspected. Regular inspections are made on various parts including the body of the plane, the engine, the tires and the various gauges. A small problem might cause a disaster. This is why the inspection is serious business.