Apply to YC (Y Combinator) - Curated collection of resources for founders applying to YC.
Pramp for Product Managers - Practice product management mock interviews with other PMs
SuccessRate - You are welcome to submit your draft application before a deadline to get alumni feedback.
The PM Interview - Practice PM Interview Questions (w/ timer).
Reject Them Softly - Rejection letter inspirations from companies
Product Management Exercises - A repository of product manager job interview exercises