Not enough information for anyone to really help you.
Did you setup XBMC to check your F: drive as a source for movies?
See Wiki: Media Sources
It's a little dated, but basically you need to add your F: drive to XBMC's sources list so it will check there for movies.
If you've done that, your files should at least show up in the files list. Post a little more information about what you've done so far and what XBMC is doing.
Someone should be able to help you with a little more information.