You'll find people are a lot more willing to help you if you show a few things:
- Code you have got so far
- (an example of the) input you used
- Error messages you got (Make sure you are using strict and warnings and if you are a beginner diagnostics can be helpful)
- Output you got (or output you want)
These things will show you have at least made some effort, and so people will be much more likely to make some effort to help you. All of this is explained in How do I post a question effectively?
Other than that, there is a lot of info on the web, so make sure you have thouroughly searched (e.g. perlio for reading files, perlre for searching the information) etc...
Updated: Updated pointer to a more positive place (Thanks to wfsp)
Just a something something...