It was just one interview that was based mostly on your resume. Basically explain the projects you listed. If you are thorough with your projects, you are good. Sometimes general questions are also asked. (like what's a BST)

It was a video interview. You had to record your answers when the prompt appeared on the screen. I believe there were about three questions. There were also videos about the company that you had to watch. This was months ago so my memory about it is foggy.