The GD/PI round of UPES is as stringent and properly chalked out as that of any other university or college. All GD/Pis are hard to crack, but you need to show some grit and determination to crack them. Your overall personality is testes in GD-PI, and you are being judged for everything that you say. So, it is important to create the perfect balance between being apparent and subtle. You should be updated about current affairs, international events, issues affecting India and the world, etc so that you can put forward your opinion and views when asked.
Give your nest shot and you will easily be able to crack both GD and PI of UPES. Be confident, dress well and put your points across like a professional.  

It is not hard if you are confident. You can follow the points given below:

Be confident in whatever you say to the GD Panel and try to be the first one to speak that leaves a mark on the person taking your GD. They will give you a topic Choose for or against the motion.

For PI speak up on those topics which you are comfortable with and have enough knowledge about it. Be calm, relaxed to say what you don't know.

Good Luck!