A goal is a measurable objective toward which one works. A plan is a set of steps or actions by which one works toward a specific goal.
Goals should be S.M.A.R.T. They should be Specific, Measurable, Attainable, Realistic and Timely. If they are not, they can lead to discouragement or a sense of failure.
Planning involves breaking down a goal into a progression of smaller, interim steps, or breaking down a finished product into smaller, component parts, so that the steps or parts are easier to approach, figure out, solve, implement, or create. Some people require fewer interim steps with greater significance while others require more steps of a smaller nature. Some people need frequent breaks or check-points along the way while others work in longer stretches with greater independence.
The challenge in creating a good plan is to find and balance approaches that best support the individual in each situation.