Hello Shubham,

Pros and Cons depend on the path of the career you want to pursue.

Pros - 

1. You are getting 2 degrees and saving 1 year.

2. You get a lot of time to prepare for Job/Placements, So generally dual people get a better job.

3. Most core companies have the requirement of dual degree for certain job openings. 

4. The paygrade of dual degree candidate is a bit higher as compared to B. Tech.

5.  You get a little bit of research exposure by doing thesis work.

Cons -

1. If you are planning to go for MBA then its a waste of 1 year except that you get an extra year for preparation.

2. Similar arguments if you are going for non-core jobs too.

3. If you are not into research work you might find the thesis work boring and hectic.

All The Best.