Standard interview process, you'll be given a problem to solve online within 45 min, then follow-up with a technical phone call. If you impress the interviewers, you'll be invited to onsite interviews.
Onsite interviews will cover both algorithms, problem-solving, design, database, and culture-fit.
My advice:
Algorithms: The questions will most likely be standard but take note of the importance in writing clean code and test your implementation. You are expected to know Big-O notation, common data structures (hash table/dictionary, tree, stack, queue, arrays, list) and the interviewer would be impressed if you can point out the reason why you pick such algorithms or data structure.
Design: Focus on solving real life problem using proper OOP. Define the classes, inheritance structure, the interfaces, and implementation clearly upfront. You don't have to know every design patterns but know the most common one won't hurt (Singleton, Strategy, Template Method, Bridge ..etc). Design for reusability and maintainability. Always ask questions to clarify the intent of the design exercise.
Database question: Depending on your role, if front-end engineer then you may not need to go through this step. For backend engineer, you're expected to write proper SQL, able to design tables with properly E-R, understand cardinality (1-to-1, 1-to-many, many-to-many), aggregations. Some advanced questions may be about LOCKs, INDEXES, CTE.
Always draw your ERD first, identify the columns of each table, write your SQL with such ERD then fine-tune them.
Culture-fit: In general this session is to evaluate whether you are smart, you are fun and you are friendly to work with? Be sincere and professional, explain how you would solve a conflict, show that you are proactive and a valuable asset to the team.
