I did 2 phone interviews. Both were 45 minutes and were coding questions. The interviews started off with a 5 minute ice-breaker, and then went straight to coding. This was several years ago, so I doubt Amazon still hires interns like this. They do, however, still offer you a full-time offer at the end of your internship if you perform well. This is how I got my full-time position at Amazon.

One online assessment and one virtual interview included a coding round and leadership principle questions; overall, the process was fairly straightforward and not overly challenging for me throughout the experience.