There are a lot of good courses available throughout the net by Andrew Ng, didactically thought through and good to grasp. There a lot of basis are explained. Several text books are available for deep learning, but Learning Deep Architectures for AI by Bengio stands out as it goes into different aspects of architecture, belief nets and so on. Most of these basics you can need for text classification. I would start there and dig down deeper on specific AI procedures with papers and conference contributions.

Dear Mohamed Sameer

Watch these lectures from the Indian Institute of Technology (IIT), Madras on Applied Natural Language Processing. Complete playlist is here.

https://www.youtube.com/watch?v=5hKxvh4RAsY&list=PLyqSpQzTE6M_EcNgdZ2qOtTZe7YI4Eedb

Apart from this you can also watch out several lectures on deep learning algorithms on this platform.

Hope you will get benefitted.

Thanks for asking.

Regards,

Gyanendra Chaubey

Have a look at the attached book and https://www.deeplearningbook.org/