The cut offs for the BTech CSE course changes every year depending on the appearing candidates performance and the paper difficulty. If you wish to estimate for the IIT CSE Cut off 2021, you can consider the link provided below:

https://engineering.careers360.com/articles/jee-advanced-cutoff-for-iits

For the previous year, IIT's cutoff for BTech Computer Science & Engineering for the year 2020, 2019 etc consider the link provided below:

https://engineering.careers360.com/articles/iits-cutoff-for-b-tech-computer-science-and-engineering

I hope this helps. Wish you a great day!