While you are on the composition panel, by pressing apostrophe (!) key will show you the area that will cut out from the footage.
The function of the key frames is to set parameters for audio, motion, visual effects and many other properties for any image or object by changing them over time. After effects is mostly used for animation purpose, and by setting key frames and after effects properties, they can move the image as if they are […]
To get into the exact spot of footage, in the control panel below the composition screen there is a tab showing time. On double clicking the tab, it will open a window where you can adjust the time and you can reach to the exact spot of the footage.