No! you are not eligible for MTech program through gate, you can apply for Integrated PhD programs/MSc programs using the GATE rank. Only after MSc you can do MTech programs. There are some institutes which offers MSc-MTech dual degree courses which you can join but you are not eligible for MTech course.

To know more about GATE visit the link below:

https://engineering.careers360.com/articles/gate

To know more about CS visit the link below:

https://www.careers360.com/courses/computer-science-course

I hope this answer helps. All the very best for your future endeavors!