I want to study biotechnology after 12th..(Please Help)?

Yes, this subject is very important and useful for future coming life. It is technical and practical subject.

just to add. Biotech is divided into 2 specialities .Either the research career(BSc,MSc,PhD,PDF) or the Industrial Career(Engineering/MBA). Now if you consider science research it could be an academic research you find (which has no commercial value or less commercial value, things like finding genes) or it could be a research within the industry where researchers try developing new products for the masses, like new drugs etc. Engineering has a PhD route too where you focus on improving or devising new processes.the normal graduate guys join to just work mechanically, no scope for research of any sort. Industry is divided into R&D, Process development, Production,QC,QA. Now if you plan to be in R&D you need to know which part of things you need to focus on.as in do you want to develop for example a new drug/product in a lab setting or do you want to establish a way of making it in bulk quantities for public consumption (commercial scale). So if you plan a new product, then incase of biotech, developing strong scientific background is important which would mean either a bsc or msc course(either way both are hopeless). Now if you plan to go into mass production, you would need to develop suitable methods of manufacturing your product and then optimising that manufacturing process. that might mean deciding on a reactor configuration or a way to optimise a purification process etc. If you plan this part, then you need to have an engineering background which can be either a biochemical or biotech b.tech. Engineering will involve maths but so will science. Most students who opt for biotech either did it based on the hype surrounding the field or just because they thought they can research something and come up with something new. Now if you have an interest in this research plan, then I would suggest to apply strongly for bsc courses alone, though the issue is that 3 year BSc are not recognised in the US and to do a phd you would need to complete an additional 2 year msc.Even after BSc or during MSc you would not be able to apply for any grant to get money to do research. hence a PhD is required which can take 3-5 years depending upon alot of factors like the country, the lab ,the guide, the topic etc. Once you do a PhD, what you could or is expected of you is to do a post doctoral research in some good lab to get a few good research findings and paper publications.Once you complete 2-3 years as a post doctoral fellow, it is expected that you would become independent and would be able to establish your own lab in some university environment by getting grants from govt agencies or other sources(I consider it equivalent to setting up a business,either way is complicated and difficult to succeed). Most PhD ppl end up as pdf's in labs and take an mba to enhance their business skills. Since you make a mention of genetic engineering, I believe your looking for more of a research careeer. This whole thing would be like 12 years of study and no pay for the whole year.. I find the whole field a waste of money.Neither graduates get paid nor are they absorbed quickly. If you do engineering, your taught more about fermenters,centrifuges,and about how to design them and operate them according to the process conditions.It is quite monotonous, but if finding a job is priority, then engineer's do get a priority over science graduates as getting into labs would mean clearing alot of competitive exams and lack of stipends. I hope this gives you a good idea.I am a biochemical engineer.In my opinion, go for commerce ;) ..life is much more peaceful. it maybe just that the grass looks greener on the other side,but I feel biotech is just a waste.