Screws for macbook pro early 2011 fan when I was cleaning my mac book's fans I destroyed one screw head shown in picture (right fan)  picture from ifixit

How can I replace it?
Drill that screw up, or other method?
And where can I buy a new one?
The fan screws are most likely 7.2 mm or 5.3 mm T6 Torx screws (the appropriate iFixit teardown will help you)

If the body of the screw is still screwed in, it could be very difficult to remove and require more specialist repair.