How do I make the boxes bigger?:
$\displaystyle \boxed{}\boxed{}\boxed{}$
The \boxed command is designed to make the box fit snugly around its contents. If you want to make a bigger box then you need to give it some contents (which you can make invisible in various ways). For example, \boxed{\phantom{\vrule height15pt depth5pt width20pt}} will give you a square box with sides 20 points (of which 15pt are above the baseline and 5pt below): $\displaystyle \boxed{\phantom{\vrule height15pt depth5pt width20pt}}$.