It was in 3 stages; computer test ( screening round ) followed by writing test ( script writing) and finally the interview in which general questions were asked. If they found you deserving they call for another interview round in which a topic is given for demo.
I applied through university. The process took 3 days. I interviewed at BYJU'S (Bhopal) in Sep 2019
Interview
Three steps: computerized aptitude test regarding basics on physics, chemistry and physics, on-paper slide designing on a topic from physics, chemistry, or mathematics, interview on subject-specific content. This was the interview procedure.
During my interview, we delved into diverse mathematical concepts, primarily from the 12th-grade JEE Advanced syllabus. The session extended for approximately one hour, featuring a mix of challenging and moderately difficult questions.
Interview questions [1]
Question 1
describe the properties of functions: "One-to-One," "Onto," "Many-to-One," and explain each concept in the context of mapping elements between the domain and codomain
Interview was held in Three stages- firstly there was screening test based on mcqs related to science , maths, reasoning etc
(2) script writing and storytelling which was written test ,
(3) interview round where demo on a particular topic was also asked
Interview questions [1]
Question 1
Questions related to mathematics concepts like quadratic equations etc