YC Interview Practice App - Get asked YC questions by Sam Altman
The Product Management guide - A book on how to create and ship products that people love
The PM Interview - Practice PM Interview Questions (w/ timer).
Xobin - Most Comprehesive Pre-Employment skills testing and Psychometric Assessment Platform.
interviewing.io - Free, anonymous technical interview practice
Intercom on Product Management - The ultimate resource for aspiring product managers