Can you all please help me with system design resources. I am very grateful to leetcode, coz the damn questions were copy pasted. So, thank you very much.

I want a solid guide for system design preparation, just like leetcode. I do have time for the onsite rounds. Any help would be extremely helpful.

Phone Interview questions:

1. Valid palindrome after deleting atmost 1 character.
2. Sliding window maximum length substring having all characters of another string.

Catch: You have hardly 30-35 min for these 2 questions. So you better solve a problem in 12-15 minutes and also handle a few counter questions and dry run the code. That was not so easy.

Good thing is you dont need to compile or submit. Code should be nicely readable and should look correct in one glance.
Rest 10 minutes go away in small talk!!