If the Option expires OTM, it will expire worthless. There will be no charges. However, if you’re a option buyer and if the Option expires ITM, then exchanges charges STT at 0.125% on the intrinsic value.
This will not be applicable if you’re a Option seller as STT is already paid when short position is taken. Please check out this post for more details: What happens if I don't square off my positions in options? - #2 by ShubhS9