We know the value of f(-4), which is 2
Let's think about a value of x in which we can calculate the value of f(x+1) using the given information (it means x+1 has to be equal to -4)
x+1=-4
x=-4-1
x=-5
Now use this value to calculate g(x)
As we said, we already know the value of f(-4), use it to calculate g(-5)