Hello gourav. 

I would like to tell you that the best books for your 12th class is your NCERT books.

But as you mentioned that you wanna know about the best guides that will help you in your 12th boards and NEET also, then they are:

- For biology - Trueman

- For chemistry - ABC modern

- for physics - S.L Arora.

These are some of the best guides that I'll prefer. 

Apart from this you can also go through the sample paper of " Arihant" this will also help you alot to get good marks in your 12th. And will also help you to knoe about the questions paper patten in boards.

Here I'm also sharing you a link that will help you to get the information about the some other good guides and sample papers also according to the different subjects. Please go through it and if have any further questions feel free to ask. 

https://medicine.careers360.com › ...

Web results

Best Books for NEET 2019 – Physics, Chemistry, Biology - Careers360

Hope this will help you!!

Good luck.