Hello Indrajeet Singh ,

For any NCERT book you can refer National Digital library of India it is an official website you can get any competition books soft copies  ,state books , Nptel lectures , Talks and webinars e.t.c . This website was developed by the Indain Institute of Technology , Kharagpur and sponsoerd by Ministry of Education government of India .

I am providing the link here for National Digital Library  go through it and get soft copy .

https://ndl.iitkgp.ac.in/

I think this answer will help you lot

All the best !!!