Hello there!
To solve those questions, you only have to substitute the number inside the parenthesis into x.
f(x) = x² + 1
f(-2) = (-2)² + 1
4 + 1
f(-2) = 5
f(0) = 0² + 1
f(0) = 1
f(1) = 1² + 1
1 + 1
f(1) = 2
So your answers are....
f(-2) = 5
f(0) = 1
f(1) = 2
Hope this helped!! :)