Determine y for a function with a symbolic variable x

I couldn't find the right solution for my question right now.

How can i determine the y-Value from my given equation at the point x?

Example, find the y-Value for x=0.

syms x;

y = x.^2;

y_0 = find(y, x==0) % that doesn't work

Answer 1

[Torsten]

syms x 
F(x) = x.^2;
F(0)