How would I solve a (F of G)(2) if the x is replaced with 2

I have two equations, and (F o G)(2)

I won't post the equations, not a cheater, just need an idea of how I could solve something like this.

So if x is replaced with 2, do I replace 2 instead of x in the F Equation with the G Equation?

Thanks.

first find f of g
for example if f(x)= x-1 and g(x)= x-2
then
f of g:
f (x-2)
(x-2)-1
x-3

now insert 2
f of g = x-3
=2-3
=-1
:D