Linux

Hello Akash,
Linux is a "must-know" for anyone interested to work in IT department. Linux is an operating system and provides sufficient tools which assist in advanced programming. On the other hand, CCNA is a networking course certified by CISCO. This course is recommended for those who wish to make make a career in the networking field in the IT sector. Ideally, I would suggest you to pursue both the courses as both are equally beneficial. Rest is your choice.
I hope this answers your question to your satisfaction. If so, kindly upvote this answer. If you have any further questions, kindly revert.

CMC Limited (A TATA Enterprise), Linux Lab Pune and Shivaji Nagar Pune are the best institutes to pursue Linux in Pune.

Linux device driver courses are part of System Programming PG Diploma courses. Very rarely this course is offered as a separate course. You can learn Linux Device driver fundamentals and programming yourselves as you must be having good C and C++ exposure during MCA.

Do Redhat Certifications from a nice institute around you.

Oh, its a wonder and it's going to be the most important skill for anyone.

Hello AS,
There are some good institute in India for CCIE like Networks Era, Network Bulls, Networkers Guru but according to your question, Networks Era is the best training institute for Cisco CCIE, Juniper and MCSE training. They have real and live devices for practicals and also have professionally experienced trainers. You can visit personally and then can decide.

Hi Abhishek,
While selecting an institute, kindly refer the following points:
1) Faculty,
2) Affiliation / Recognition
3) Course Material
4) Quality Education
5) Fees
6) Infrastructure
7) Success Rate
8) Placement
9) Top recruiting companies
Also, if possible go through the alumni speak section to get an idea what the alumni thinks about the institute.
Hope this information helps. Please feel free to revert.
Wish you luck.