I went to a party last night.
Last night, I was so excited that I barely slept.
Night is the time when monsters crawl up through the floor to have tea parties under my bed.
The kanji and the word are exactly the same. That means they share meanings as well.
Since this word is made up of a single kanji, it should use the kun'yomi reading. When learning the kanji, you didn't learn that reading, so here's a mnemonic to help you with this word:
It is the night, but it is your (よる) night.