find an equation of a parabola given Focus (0,3) coordinate point on parabola is (2, 5).

There is not enough info for a unique solution. There are many parabolas that could fit this criteria.

One would be y=\frac{5}{4}x^{2} if it's axis were parallel to the y-axis.

The parabola could also have its axis parallel to the x-axis and have another equation that satisfies the conditions.

(5-k)^{2}=4p(2-h).

(h,k) are the coordinates of the vertex. P is the distance from the vertex to the focus.