Hello

If I am not wrong, BEnnett University provides BTech in Engineering Physics while CU provides Physics Hons.

After BTech you will probably want to get placed or qualify GATE and go for MTech after which if you want to enter research field you will have to go for PhD (the minimum time it will take for you to do this is 11 years).

In BSc hons option, after completing Bsc hons you may go for IIT JAm or DUPGET or BHUPET or other entrances along with GATE and get into MSc in Physics after which once you qualify CSIRNET exam. Onqualifying CSIR NET if you also qualify for JRf (Junior Research Fellowship) you automatically become a rsearch scholar (and you can continue with PhD after which you will become a researcher). (it will take you 8 to 10 years atleast)