Do you have the license plate bracket for the front of the car? Sounds like there isn't one there - hence the little bumps on the bumper cover. You could just use some self-tapping screws and drive the new plate onto the front bumper - don't drill - too easy to drill too deep (into the center support beam). Unless you want to drill some little pilot holes to get it started - that case probably OK.
But I'd try and find a bracket - makes for a much cleaner install - pushes the plate and frame away from the bumper so as to not scratch up the paint in that area. The dimples on the bumper help you align the bracket - but they don't actually match up to the holes. I know on the one for my RAV4 - there where two sets of holes, one set for the bracket to the bumper and the other for the license plate to bracket. I drilled two relief holes behind the ones for the plate to bracket - so that the screws for the plate would not pry the bracket off the car. The bracket to bumper was handled with some self tapping screws.
Here is the example PDF that I followed to install my bracket. The one for the Corolla will be very similar. http://rav4world.com/2009_photos/2009_license_plate_bracket.pdf