Graphing quadratics by hand is an important exercise because it helps us understand the parts of a quadratic equation. These are two different lessons that hit the same point, using the structure of the equation to graph the quadratic equation onto a coordinate plane and identify key parts of the graph.
While in the future, you will be using a graphing calculator to accomplish this task, for now, graphing by hand allows us to highlight the key features.
The links above will lead us to a better understanding of vertex form when we get there and the value it provides for us moving forward. Remember, the vertex is the maximum or the minimum of the parabola.