HELPPP?!!! What is the value of f(-2) and f(3)

Step #1 for both: figure out which interval your x-value fits into.
For f(-2), x=-2 and -2 fits with x ≤ -2, the top interval.
For f(3), x=3 and 3 fits into -2 < x ≤ 3, the middle interval.

Step #2 for both, plug in your x-value to the piece of the function that fits with that interval.
For f(-2), we know x≤-2, so we use 2x+8 to evaluate x=-2.
For f(3), we know -2
f(-2) = 2(-2)+8 = -4+8 = 4

f(3) = (3)^2 -3 = 9-3 = 6