Can you help me measure the vertical and horizontal lengths of this wall?
Vertical and side (horizontal). That means you have the length and width and the vertical and horizontal.
This is a jukugo word that usually uses the kun'yomi readings of the kanji. You should be able to read this on your own.
Note however, that there is a less-common on'yomi reading, じゅうおう, which is used in some idioms. It's good to know this reading exists, but you probably won't come across it very often.