CS0120 OBJECT REQUIRED

I’m working on a robot controller and is giving me error cs0120 an object reference is required for non-static field, method, or property rigidbody2d. Velocity. Every correction to rigidbody2d gives me a velocity error every correction to Velocity gives me an entire script error

First result from google for that error code describes the issue from the developer of the language. The second result is from one of the many similar questions on this very site that explain the issue and how to fix it. The search bar is your friend.