Class 12-science

Hello Abhishek,
There are many modes through which you can join ISRO as Scientist or Engineer. After 12th or during 12th, you can appear for IIST exam (Indian Institute of Space Science and Technology (IIST), Trivandrum ). To know details of this exam pl see the IIST web site www.iist.ac.in. IIST graduates above a certain pass percentage cut off in final B Tech exam are directly absorbed in ISRO system as Scientist/Engineer -SC grade.
One can also join ISRO after finishing B Tech from university system. For this they have to appear for ISRO centralised recruitment. The advertisement for this is often published in national newspapers.
You can also join ISRO after completing M.Sc, M Tech and Ph D. in science subjects like Physics, Maths, Electronics, Geology, Geophysics etc. Advertisement for such positions also given in national newspapers.

Hi Aashika,
There are many pros and cons of studying through distance or in SOL. You have to keep a number of factors in mind while deciding. Though distance education degrees are increasingly recognized all over and you can study anytime - anywhere, also saves a lot of money, working while studying there still exist a question on its credibility and recognition amongst employers and further education particularly in India. It is difficult to suggest if it is good or bad since it will depend on your own priorities and needs. Keep a check on the recognition, UGC approval, employment of students, your career plans if any and decide accordingly.