The problem asks to find the value of $f(3)$ for the function given as:

$f(x) = x^2 + 7$

To solve for $f(3)$, substitute $x = 3$ into the function:

$f(3) = 3^2 + 7$

$f(3) = 9 + 7$

$f(3) = 16$

So, the value of $f(3)$ is $16$.

Would you like me to explain further or assist with additional related questions? Here are some follow-up questions:

1. How do you evaluate functions with different types of inputs?
2. What happens if the input is negative? For example, what is $f(-3)$?
3. How would you solve $f(x) = 0$ for the given function?
4. How does this function behave for large values of $x$?
5. Can you graph this function to visualize its behavior?

Tip: Always substitute the given value carefully and simplify step by step to avoid errors.