Hi

IIT KGP offers admission on the basis of 4 criterias. They are :

• through GATE
• 
  
• B. Tech students graduated from IITs with at least 8.00 GPA
• 
  
• Sponsered Applicants

NET qualified candidates

If you want to join through the Gate exam, you can check the cut offs of previous years for your interested course through this link https://engineering.careers360.com/articles/gate-cutoff-for-iit-kharagpur

hope this helps!