Hi there. 

Cut offs vary every year depending on a lot of factors. Looking at the previous year cut off patterns might give you an idea of how much you need to score to get into the desired branch of IIT Kgp. 

Check the link below: 

https://www.google.co.in/amp/s/engineering.careers360.com/articles/jee-advanced-cutoff-for-iit-kharagpur/amp

Hope this helps.