According to me the following courses you may opt after completing your 12th from science stream the names of the courses are as follow:

Engineering As B.tech in :
Aeronautical Engineering
Automobile Engineering
Biomedical Engineering
Chemical Engineering
Civil Engineering
Computer & Communication Engineering
Computer Science & Engineering
Electrical & Electronics Engineering
Electronics & Communication Engineering
Industrial & Production Engineering
Information Technology
Instrumentation & Control Engineering
Mechanical Engineering
Printing & Media Technology

Bio technology courses :

B. Sc. in Biotechnology
B. Sc. in Biotechnology and Bio informatics
B.E. in Biotechnology
Diploma in Biotechnology

Professional degree Course :

BCA
BSC IT

or you may opt some polytechnic diploma courses .