HELP
MacBook Pro (13-inch Mid 2012)
Posted on Aug 23, 2016 8:54 PM
Q: facetime does not work on macbook pro mid 2012
You have essentially told us nothing ... other than you are using a Mac (even though you posted in the iPad community).
So, without additional information, see:
FaceTime for Mac: Troubleshooting FaceTime - Apple Support