Varies from position to position. Some places have up to 4 rounds of interview or more. Some maybe just 1 or 2.

Not exhaustive. Typically they will ask you to share about yourself. What your strengths and weakness are. Why you choose this company over something else. And also skills based questions if you are applying for a technical position/internship.

Do prepare some questions that you’d want to ask during the interview itself. Or look up on what they do, recent news related to the company that you can raise up during the interaction.

Outcome timing varies as well, can take 2weeks or more depending on how competitive the interview process is. But if they think you fit the description of what they look for in an intern, you can get a reply as short as within 3 working days.