Hello, if you are interested in these branch then go for it otherwise you can also look for other branches like Cs / It which mostly focus on coding.

If you work hard and  learn subjects then it will increase your marks and physics, chemistry are not so tough just revise them by making notes and formulas.

Refer to this link it will help you

https://www.careers360.com/courses/instrumentation-engineering-course

All the best.
Hope this will help you.