How do I select part of an image without selecting the whole image?

[CrypticMeriter]

So I import an image to the stage, but now I want to select part of an image so I can animate it. So I select it with the Lasso Tool, Polygon Tool, anything, but no matter what I do, when I finish the selection, it selects the entire image. What do I do? 

[ClayUUID]

Asuming you're talking about a bitmap, you can break it apart, which turns it into a bitmap-filled vector shape. You can then manipulate this shape in all the usual ways.

That being said, this is a terrible workflow. Any bitmap images you want to animate individually, should be imported individually.