The given parabola is

The vertex of this parabola is (0,0), the origin of the coordinate system.
The focus is determined by p. We know that 4p = -4, which means p = -1.
So, the focus is (-1, 0).
The latus rectum passes through the focus perpendicularly, which means its ending points are (-1, 2) and (-1, -2).
The parabola is shown in the image below.