It will virtual and tell to answer the script for atleast of 4 rounds and in reach round consists of telephone round, video call round and depends on your performance.

The entire interview process will be in telugu. In a very decent manner. There is no need to worry about English. After applying, they will contact you through WhatsApp with in two weeks, they will send you a demo call discription then they will ask you to record the video by your self like talking with a student, you need to sent the video in a Google form which is sent by them. If your performance is good in that video they will shortlist you and contact you to assign a interview in that interview also you have to tell them same story which is sent to you. The interviewer will play a role as student and you are the bda and you need to talk like a professional BDA. That's the last step of process ,if they feel like you are suitable to that role. You will get a call from them as you selected.