I want to work in the field Bionics in the future.. is it a correct choice do btech in electrical engineering?
Yeah.Its also a way to be a bionics engineer.After B.Tech go for M. Tech with bionics specialisation to achieve your goal. Actually You have three options either take any engineering sciences course in bachelor's and then do bionics for specialisation or take bionics from bachelor's itself or take some biology related bachelor's and do bionics in specialisation. I suggest you to take some engineering science as bachelor's suggestably mechanics, or electrical and then do bionics in specialisation because bionics is mostly about robotics, material science and biology which can mostly be covered in either mechanical engineering or electrical.
All the best for your career.