i am able to attempt 2 sets only. whenever i read sets i preassumes that i cannot solve this set what shoukd i do

Hi
The reason you feel you won't be able to solve the set might be you are not confident, try to be aware of your strengths very very well for example if you like arrangements solve arrangements set, if you like tables attempt tables set first, just try to attempt first two sets which are your strong suit and once you are done with the 2 sets, read the remaining sets, go through the questions asked as well if you see there can be cases then you can avoid that set for the time being and go for the next set . This is the fear which you have to overcome , attempt atleast 1 sectional in every two days practice as much as you can that will surely help you in improving your confidence.

overcome the fear.