First, for end behavior, the highest power of x is x^3 and it is positive. So towards infinity, the graph will be positive, and towards negative infinity the graph will be negative (because this is a cubic graph)
To find the zeros, you set the equation equal to 0 and solve for x x^3+2x^2-8x=0 x(x^2+2x-8)=0 x(x+4)(x-2)=0 x=0 x=-4 x=2
So the zeros are at 0, -4, and 2. Therefore, you can plot the points (0,0), (-4,0) and (2,0)
And we can plug values into the original that are between each of the zeros to see which intervals are positive or negative. Plugging in a -5 gets us -35 -1 gets us 9 1 gets us -5 3 gets us 21
So now you know end behavior, zeroes, and signs of intervals
f(x-2) determines a horizontal translation 2 units to the right. Since (9,-8) is the point for f(x) then f(x-2) will be the point (11,-8) where 9 has moved two units to the right 11.