If such person use it or attempt to use it for getting admission in any institution for getting the reservation benefit or uses it to get some government service he can face punishment upto 3 years imprisonment & fine u/s. 198 IPC. You can inform the authorized authority regarding the fake certificate along with evidence that will show its being fake, the authority will then examine the evidence provided by you & if it found that such certificate appears to be false will officially file criminal complaint in the court for the prosecution of such person who has used it or attempted to use it.