Answer
right;
$4$
Work Step by Step
RECALL:
The function $y=f(x-h)$ involves a horizontal shift of either $h$ units to the right of the parent function $f(x)$ when $h \gt 0$ or $|h|$ units to the left when $h\lt0$.
The given function has $h=4$.
Thus, its graph involves a 4 unit-shift to the right of the parent function $y=x^2$.
Therefore, the missing expressions in the given statements are:
right;
$4$