what should i do after 12 (having maths stream) ? B.TECH OR Bsc IT

Well, there can be many aspects to be considered while choosing a branch (stream) for B.Tech. You have to choose the stream as per your interest. No branch is less or more important, each of them has its own importance, it solely depends on you, in which stream you want to make your career. See ther

B.Tech of course is better than B.Sc IT. So, if you've to chose in between these two, go for B.Tech.