Hi Rahul, you can undoubdtely change your stream after 12th. For example if you are studying commerce in standard 12th, then you can easily go in lines like Law, Journalism, Fashion designing, hotel management etc.

But, there are some courses in which some subjects or streams are required. for example, for Bachelor of fashion technology (B.F. Tech), one needs to have 10+2 with Physics, Chemistry and Maths. But otherwise for Bachelor in Design (B.Des.), one should have completed 10+2 from a recognized Board of education.

I can guide you in a better way, if you can tell me in which is your current stream and which is the stream that you want to switch?