Hello aspirant,

When preparing for UPSC exam studying from NCERT is very important. So having NCERT books is very important, but if you don't have them then you can go to cbse.nic.in and you can get free NCERT books in pdf form. And for UPSC study material I have provided a few links below which you can go through:

• https://iasexamportal.com/ebook
• https://www.clearias.com/ias-study-materials/
• https://www.civilserviceindia.com/study-material.html

Hope this helped.

All the Best!

Thank you.