Please be much more detailed about what you're trying to accomplish. From such a terse post, we can't possibly know what you need.
For now, all that I can do is suggest that you go through the basic learning materials here:
I admire Todd's politeness on this as he is staff, but this has to be one of the most undetailed "help me now" posts I have ever seen
You know what you mean. No one else knows what you mean. Expand how? What picture? Is it in a nested comp? Pre-comp? What kind of picture? Can't help unless they/we know more.