NDA

You can find these questions papers from either UPSC official website or any third party websites like:

https://www.shiksha.com/exams/nda-exam-question-papers

https://oswaalbooks.com/pages/nda-free-resources-for-2025-exam

https://www.centuriondefenceacademy.com/blog/nda/nda-1-2025-official-question-paper-of-maths-gat/

Yes sure you can do the preparation of NDA with pursuing class 11th. Strengthen your maths and focus on english communication also.

Best of luck. 

No, You will not be eligible for NDA exam in 2027 as you'll be over age and It requires students to be born between 06/07/2008 and 01/06/2011.

You'll be eligible fir the NDA 1 2026 examination

No, you do not need to attend a higher institution before applying for the National Defence Academy (NDA).You have passed or are appearing in the 12th class (or equivalent) examination are eligible to apply for the NDA because you need to provide your passing certificate and mark sheet at the time of the SSB interview. 

YouTube is providing you all the study material in free. You just need selected material for preparation of your dream. There are many channels for NDA exam preparation but some well known YouTube channels are :- wifistudy, Maths jugad se, coaching daddy and defence wallah. Go and start your praparation. All the best for your journey.