The mask is the technique by which you can select the specific area within the image or picture you want to modify while leaving the rest of the image steady, the short key to select image in mask is Ctrl+T.
In the composition panel, select rotation option by pressing ‘r’ on your keyboard. Now on the right hand side you will see numbers, which show how much degree you want to rotate the picture. You can rotate the picture by increasing and decreasing those numbers.
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.