Are you are asking how to delete an Inform project from your computer? If so...
Go to the folder where your Inform projects get saved (if you're not sure what folder that is, check to see what folder opens when you start Inform and click "open an existing project").
Inside this folder there should be two folders associated with each project--one folder ending in .inform and one folder ending in .materials, but they'll both have the same filename otherwise--and you can delete those the way you'd delete any other folder, by dragging them to the recycle bin or what have you.
