In the Mac Finder, you can get info on any file, folder or application by highlighting it (by clicking on it once), and then holding down the Command and I keys at the same time. I use this all the time to determine the size of a file, assign sharing and editing permissions to it, and set the preferred application to open it.
I recently discovered that you can use the Get Info command directly within Spotlight. Simply search for the file you’re looking for in Spotlight, highlight it, and hold down Command and I at the same time. This is a very speedy way to get info on any file on your Mac!