I enjoy poetry every day.
Fugu's secret skill is composing marvelous poetry.
Shiika means Japanese poetry and that generally includes kanshi, waka, or haiku.
A poem song is poetry. It's not quite a song but I think you can make the connection.
This is a jukugo word, which usually means on'yomi readings from the kanji. You know these readings, but there's usually an extra い in the middle. Don't worry, しか is totally fine too, but しいか is more common. You got this!