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:
Tell me about your country. Now imagine that everyone in your country has cool knees (くに). That's because the national dress code is shorts, so everyone's knees get chilly. That why they have cool knees. You could also imagine cool knees in the sense of trendy knees. What makes for cool knees, in your opinion?
Which country are you from?
I thought this country was safe, but now I'm disappointed.
In my country, there is a shop that sells apple pies made by a cat.