Which engineering branch shall I choose? What is the difficulty level of various engineering branches?

It depends upon you interest. If you love computers, learn it better. It depends upon your field of interest. And always remember, engineering is not that easy as people think. You have to study hard. It only gets interesting if you like what you're learning.

Choose mechanical only if you have the mmechanical aptitude I.e you like to work on the big machines.Computer sc eng has a wider scope as it van cater to vast range of industry.AS far as the difficulty level....nothing is difficult accept to mke up ones mind to achieve the goals .