For joining in ISRO -SC (entry level). Basic education qualification is Msc or Btech. Msc can be in Physics, chemistry or mathematics. After Bsc physics you can only join as Technical Assistant but ISRO allow you option of part-time/correspondence study, after completing Msc you can get promoted to Scientist-SC. After completing you BTech/BE/BSc you can apply for ISRO . I SRO advertises jobs vacancies on its official website for scienctist and many other posts, so follow its link to stay updated. You will also have to appear for ISRO exam and syllabus will be available on their site.
I hope it helped you if you have further queries you can ask here .
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile