Government & Defence Entrance Exam

In order to secure admissions through this entrance exam, candidates need to fulfill multiple eligibility criteria of UPSEE 2018, which are as listed below:
UPSEE Eligibility Criteria for B.Tech programmes
Candidates are eligible to apply for admissions into this course through UPSEE exam if they:
Have completed their 10+2 or intermediate exam from UP board or its equivalent from a recognised board or university with a minimum aggregate of 45% with physics and mathematics as subjects studied by them. Candidates belonging to the SC/ST quota need to secure an aggregate of 40% in their 10+2. Candidates should have secured this percentage without getting any grace marks from the state or central education board. Important:
In order to meet the eligibility criteria for UPSEE 2018, candidates should have studied one of the following subjects Biology, Chemistry or Biotechnology as an optional subject.

You are going to get many opportunities after 12th with PCMB, I will mention all Entries which you will get in ascending order, with the one which comes first in first place. NDA Entry:- UPSC Conducts NDA Exam for 12th Pass and Appearing Students, twice a year. You need to keep the track of Notification on Welcome to UPSC | UPSC. Type of Commission is Permanent Commission. Following will give you the tentative date of release of Notification. The valiant boys could be part of the Indian Air Force family by applying for NDA ( National Defence Academy)
Candidates, short-listed for Indian Air Force after the initial selection procedure, go through a rigorous three-year training regimen at the National Defence Academy at Khadakwasla, followed by specialised training at one of the training establishment. Thereafter, they are Commissioned as Permanent Commission Officers and posted as pilots at any of the Air Force Stations. To be in the National Defence Academy
You can join NDA by taking the exam conducted by Union Public Service Commission (UPSC). This exam is conducted twice a year in all major cities throughout India. Eligibility Criteria
Age - 16 to 19 years (at the time of commencement of course)
Nationality Indian
Gender - Men only
Educational Qualifications - 10+2 with Physics and Mathematics. Appearing final year students can also eligible to apply. Advertisement Schedule - June and December. (Advertisement is released by UPSC. Visit Welcome to UPSC | UPSC)
NDA is the only option after 12th to join Indian Ari Force, however, if you do your graduation or Engineering, many opportunities come your way. CDSE Entry: - If in case you were wise and didn't opt for engineering and instead got into B.Sc. course, or another corresponding course, you can give CDS Exam, again conducted by UPSC twice a year. Kindly note, even engineers can apply through CDS Entry, actually, they can apply everywhere. :P
AFCAT Air Force Common Admission Test. oFor all entries other than CDSE and for all branches, candidates have to undergo the AFCAT. - the test is conducted twice a year in February and August. - Advertisements inviting applications for AFCAT are out in June and December. Candidates are to apply as per the advertisement. - The test is conducted all across India by the Indian Air Force
NCC entry
- Air Sqn NCC Senior division C certificate holders are to apply through DG NCC.

Hi,
Yes, the books are very helpful. Rest, it is up to you whether you like to learn from books or you think that classroom trainings are better. Some people like to learn under the direct supervision of a teacher and in that case, you can opt for coaching classes. If you are looking for some good books for UPSC preparation:
1. Indian Polity for Civil Services Examinations by M. Laxmikanth (Polity).
2. Indian Art and Culture by Nitin Singhania (Culture).
3. Oxford School Atlas by Oxford Publishers (Geography).
4. Certificate Physical and Human Geography by Goh Cheng Long (Geography).
5. Indian Economy by Ramesh Singh (Economy).
6. India Year Book (Current Affairs).
7. A Brief History of Modern India by Rajiv Ahir (Modern India).
8. NCERT Books.