You can read the points from the graph:

Or, simply plug into y=x^2-4:

For x = 0 

y = 0^2 - 4

y = -4

(0, -4) is one point of the graph.

For x = -2

y = (-2)^2 - 4

y = 4 - 4

y = 0

(-2, 0) is another point of the graph.

For x = 2

y = 2^2 - 4

y = 4 - 4

y = 0

(2, 0) is another point of the graph.