5 stages, 1 initial task, had basic SQL and DSA questions. Followed by a 15-minute call with an HR representative, which was very smooth; she's nice and patient. Followed by a technical call with a senior engineer, he'd provide you with some Java code to review and correct. Familiarity with good coding practices, as well as basic Design patterns and OOP concepts, would be helpful in this context. Followed by a systems design round, just have a good understanding of how to design and scale enterprise-scale backend systems, and understand the tradeoffs and critical points. The final stage is a chat with a C-level engineer, a pretty chilled guy, a very good conversationist, I'd advise that you have intricate understanding and perfect memory of things you have done in the past, even if you weren't the one that did them, as long as it is part of the system you contributed to, understand how they work.
Generally, there were 5 long rounds, but it was an okay process.
In addition to whatever you are studying to prepare, go through the questions they have asked in the past (here on Glassdoor) and practice them.