I’m waiting for the water to boil.
This word consists of kanji with hiragana attached. Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means boil, so the verb version is to boil. It can also be used to mean to get excited, because you're boiling with that excitement.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn this reading yet so here's a mnemonic to help you:
What do you want to boil for dinner tonight? Walrus (わ). Boiled walrus is a delicacy where you're from, and the only way to be able to eat its yummy walrus flesh is to boil it for a long time until it's soft. Mmm smells good.