SDE1 Backend interview at Booking.com, System Design interview in ~8 days - never done System Design. What should I realistically prep?

I have an SDE1 backend interview at Booking.com in about 8–9 days. Round 2 is System Design. I have 1.5+ year of industry experience, but my current role is pure C++ development

I have an SDE1 backend interview at Booking.com in about 8–9 days. Round 2 is System Design. I have 1.5+ year of industry experience, but my current role is pure C++ development and I haven’t worked much with typical backend concepts (APIs, DBs, caching, etc.). I’ve also never done system design interviews/prep. Most of my prep/strength so far has been DSA and coding problems. I’m trying to use these 8 days as efficiently as possible. At an SDE1 level: * What backend basics should I definitely cover first? * What level of system design depth is expected (and what can be skipped)? * Any genuinely beginner-friendly resources? Not aiming to ace it - just want to avoid crashing and burning. Thanks in advance.