The focus of a parabola is (0,−2) . The directrix of the parabola is y=-1 .

I assume you need the equation for the parabola

The vertex  lies at   (0, - 1.5)

Since the directrix is above the focus....the parabola turns downward

p =   l  -1 - - 1.5 l  = l .5 l  =     =   .5

So...we have this form

4p ( y + 1.5) =  - ( x - 0)^2

4(.5)(y + 1.5) = - x^2

2 ( y + 1.5) = -x^2

y + 1.5 =  -(1/2)x^2

y =   -(1/2) x^2 - 1.5

Here's the graph :  https://www.desmos.com/calculator/kqbcr8utzm