Hello Sreriyal,

Top colleges where you can pursue M.Tech in Computer Science in Northern India are mentioned below:

• Thapar Institute of Engineering and Technology, Patiala
  
• Lovely Professional University, Phagwara
• National Institute of Technology Kurukshetra
• Punjab Engineering College, Chandigarh 
• Chandigarh University, Chandigarh 
• Dr. BR Ambedkar National Institute of Technology Jalandhar 
• National Institute of Technology Srinagar

For more colleges refer the link given below

https://engineering.careers360.com/colleges/list-of-engineering-colleges-in-India?f%5B0%5D=sm_college_course_level%3APG&f%5B1%5D=sm_college_degree%3AM.E%20/Mtech.&f%5B2%5D=sm_college_state%3AChandigarh&f%5B3%5D=sm_college_state%3AChandigarh%20Tricity&f%5B4%5D=sm_college_state%3AHaryana&f%5B5%5D=sm_college_state%3AHimachal%20Pradesh&f%5B6%5D=sm_college_state%3AJammu%20and%20Kashmir&f%5B7%5D=sm_college_state%3APunjab&f%5B8%5D=sm_course_offered%3AComputer%20Science%20Engineering