Hey - what the.....r u saying!.  Do u think you are the first to graduate from US.  The way you are asking" Hello Sajha Does any one know about OPT?".  Shame on you. Your degree didn't teach you  how to present in public. You better learn the manner otherwise you can't do anything in this competitive world.

As a human I must answer  your question:

Only one OPT is given  for each degree( Level).