Use the vertex form y = a(x - h)^2 + k. With vertex (h,k) = (0,1) this becomes y = a(x - 0)^2 + 1 = a x^2 + 1.
Plug in the point (-6,-2):
-2 = a(-6)^2 + 1 = 36a + 1.
Subtract 1: -3 = 36a, so a = -3/36 = -1/12.
Therefore the equation in vertex form is y = -\tfrac{1}{12}(x - 0)^2 + 1, which simplifies to y = -\tfrac{1}{12}x^2 + 1. Because a = -1/12 < 0, the parabola opens downward.
Quick check: at x = -6, y = -1/12(36) + 1 = -3 + 1 = -2, which matches the given point.