Hello Lovish,

Yes there are alot of coaching classes which provide coaching for the written examination as well as the SSB interview. Some of them are as follows:

1. Olive Greens, Chandigarh.

2. Apex Careers, Pune.

3. Tara insitiue, Mumbai.

4 Gravity Institue , Delhi

5. Balnoi Academy, Delhi/Jaipur/Dehradun

In India there are many coaching institution to the students who wants to crack NDA exam.
Some of the very famous institutions are as follows:

Baalnoi Academy Cavalier (p) ltd, and CMI.

Pathshaala, Aggarwal Academia

Aim and achieve, Delhi

Good Luck!