PayPal interview questions

Two level of interview Round-1: React and DSA question in react some you need to fill the missing logic for the given component. In DSA for me they asked for LRU cache problem. Round-2: Design system. Question start from DNS, security, CDN, cookies handling, complete web application architecture from the browser to backend storage which involves load balancer, cache, data transfer mechanisms like web sockets, long polling, some of the questions like the give specific feature and you explain the functionality requirement in both frontend and backend like what the data you get from the user how's your frontend look like which method you efficient one transfer data from frontend to backend and why?, how can store data in table in which relation order. They asked backend too when comes to architecture and feature concept explanation.