average student qualify upsc exam or not

Definitely, any aspirant could qualify this exam. It just needs that fire in you to achieve this. It doesn't matter what is your academic background if you want to do this just follow the correct strategy, best time management, and should take test series seriously. Analyse your mistakes in the test series and try not to repeat that mistakes in the next test.
Work smart with passion. Have confidence in yourself. 
Cut yourself from the social media and do your dedicated preparation. Do not listen to anyone that you cant do it. it's only you who can push yourself to this.