i wasnt understading RC's i couldnt even get anything correct , anyone suggest me how to crossabove the cutoff or min 6-8 questions

Scoring good in VARC section is a threefold problem. Fix your attention span and expose yourself to good thought processes, which is active reading of good passages/articles which you can get in sites like AEON, The Guardian etc. You have to -
1. practice reading,
2.then learn to solve RCs individually.
3.once you get a hold of these 2 things, practice sectionals. Sectionals take into account your set selection, attention span, timing skills.
Tip: When reading passages, read comfortably, you just cannot increase your comprehension speed magically. A good metric is to read at your speaking speed, consider you are having a conversation with the passage. That is your comprehension speed. Let us say you take 10 mins to solve an RC, then what you should aim is read the passage with understanding for 7-8mins, you know your pace, and then answer the questions in the remaining 2 mins. Warning: This number is a placeholder, never time yourself like that, things are mostly variable, this is just a placeholder number.
What I meant to say was that you should devote majority of your time in understanding the passage well.
On top of that, it will take you a certain number of iterations. Just don't expect yourself to do well right from the 1st sectional. Take as many sectionals as possible, toppers take around 50 sectionals. So, 50 iterations are really good to fixate your strategy.