I have curated the list of system design HLD questions after going through several blogs, books and youtube:

1. Rate Limitter
2. URL Shortener
3. Web Crawler
4. Notification System
5. News Feed System (Instgaram, Facebook, Twitter)
6. Chat System (1:1 and group)
7. Search Autocomplete system
8. Youtube
9. Google Drive
10. Uber
11. Tinder
12. Spotify
13. Bookmyshow
14. Goibibo/Skyscanner
15. Flipkart/E-commerce
16. Leetcode
17. Logging System
18. Zoom
19. Google Pay/UPI
20. Nearby Friends
21. Google Maps
22. Ad Click Event aggregation
23. Airbnb
24. Real time Gaming Leaderboard
25. Stock Exchange

Books:

1. System Design Interview Volume 1 and 2 by Alex Xu
2. Designing Data-Intensive Applications by Martin Kleppmann

YouTube Channels

1. Hello Interview - Tech Interview Preparation - https://www.youtube.com/@hello_interview/videos
2. Exponent - https://www.youtube.com/playlist?list=PLrtCHHeadkHp92TyPt1Fj452_VGLipJnL
3. Gaurav Sen - https://www.youtube.com/playlist?list=PLMCXHnjXnTntETbhRNiGMGqyrXlMQxwBO

⬆️ Kindly upvote, if this helps