Hiii

For being an engineer Maths is compulsory, but if later you will wish to become a doctor then for NEET exam, biology has to be main subject. In this case you can take subject combination of PCMB i.e Physics, Chemistry, Mathematics and Biology and ofcourse english is compulsory. So by this way you can get opportunity to apply both for engineering as well as all the medical and science related courses in future. 
Hope this helps. In case of doubt feel free to revert back.

Thanks!