The distance in a story is measured in terms of time, space, and plot developments called complications. Each scene needs to have a point or purpose. It can present a plot development, demonstrate a facet of a character, or show impact of what comes before, and lead on to what will come later. How many scenes will depend on the number of major complications your plot contains. Each major event should have its own scene showing what takes place.
Transitions are the links between scenes.
They allow the reader traveling over this bridge to get from one to the other without being jarred. Without them, the story becomes scene, bump , scene, bump , scene, bump . When driving over a bridge you might be aware of the where each span joins with another. When reading a good work of fiction, the reader should not be aware of these scene joins. New writers often omit transitions so the reader is bored, jarred, or confused and loses their involvement with the story and leaves.