I had an initial phone interview, which was pretty standard- I.e tell me about yourself, your experience, explains the company a bit, explains the role. My second interview consisted of four, 30 min long video chats with a different person every 30 min. Every single one of them asked the exact same questions and asked if I had any questions. I found it difficult to keep coming up with questions, but I made it work. The last interview was in the office, presenting to two employees, a presentation of yourself, why glassdoor, why you're a good fit for glassdoor, good traits, etc.- essentially selling yourself and explaining why you would make a great fit for the SDR role.