Plot is what happens.
What your characters do to deal with the situation they are in. It is the sequence of events that grow from an initial incident that alters the status quo of the characters.
These events are presented and organized as scenes and sequels with an emphasis on causality. The first scene must trigger an event that follows and so on down the line. Each scene must contain some conflict and It must trigger a subsequent scene.
There must be a climax, and then resolution.