An exit is the way out of somewhere, or the way to leave. An exit might be a place or something you do, for example "he exited the room".
The opposite of an exit is an entrance.
Flitting means to move quickly from one place to another, the way a small bird flits between branches.
Granite is a common, very hard rock that is widely used for building things. It is formed from molten rock (magma) as it cools.
Granite has a coarse, crystalline structure and is a mix of many different minerals. Because its composition can vary so much, granite can be found in a huge variety of different colors.