Hello Adarsh

Yeah!!It's a best idea to join in graphic designing after b.tech because there are many oppurtunites in this field so,you can easily find job with a good income.As your doing the job which you are interested you can concentrate more on it and could reach to greater heights.Only some people will be having talent to do such kind of jobs.so,i think that it is a good idea to do graphic designing after b.tech.

ALL THE BEST!!!