Below are some CAD and FRC design resources that I have found. If you find any other resources that are helpful, feel free to add them!
General Onshape/Design
Onshape Beginner Tutorial
Onshape Sketching: Tips and Tricks
Designing an FRC Gearbox
How to use JVN Calculator
Another JVN Calculator Guide
Chain and Belt Overview
Other Teams’ Robots
Spectrum Design Reviews
Spectrum CAD Collection
Nick Aarestad Design Reviews
Behind the Bumpers
FRC Specific CAD Trainings
Nick Aarestad
973 Ramp Videos
3005 RoboChargers Class
Spectrum Trainings
Spectrum Recommended Readings
Mechanisms
Designing a West Coast Drive
Designing 2020 Intake
Another Video Designing 2020 Intake
Cascading Elevator Design
Greyt Elevator Exploration
Shooter Design Process
FRC Mechanisms Encyclopedia
Linkages
Linkages: Basic Linkages In Onshape
973 RAMP - Designing linkages with sketches
Modeling 4 Bar Intake for FIRST Robotics