urgent query pls help

i am a ca final student and is thinking of pursuing CS as well..so thinking of astartng it nxt year..
bt i hve heard dat a practice of only one thing CA or CS can be done n not both..is it true?
pls help me as m confused
n den wat is d benefit of doing cs alongwid ca..n so many students do it????

kindly give some more gud options to do a course along with ca..
MBA?
ICWAi?
or any other course wich i can start

pls reply
thnx in advance