Hey there!

You get admission in IITs on the basis of your JEE Advanced ranks only. It does not depend on your JEE Mains ranks. So, you can surely get IIT KGP with your rank. For more information regarding the previous year opening and closing ranks of various branches in the previous year and the years before and the branches you can get with the rank you have secured, you are advised to visit the following links:

https://josaa.nic.in/Result/Result/OpeningClosingRankArchieveN.aspx?Year=2018

https://josaa.nic.in/josaaorcrarchieve/Result/OpeningClosingRankArchieveN.aspx?enc=N9lE47fIvQCtn+Sq4k3AR/PB9WcjYR9Ghf4gYFx/r3w=

https://josaa.nic.in/Result2016/result/OpeningClosingRank.aspx

Hope this helps. All the best!