Castle
noun
The kanji and the word are exactly the same. That means they share meanings as well.
The reading is the same as the one you learned with the kanji.
この城の中では、飲食は禁止です。
Eating and drinking are prohibited in this castle.
今でも残っているお城は、全て観光名所になっています。
The castles that still remain have all become famous sightseeing spots.
もし宝くじが当たったら、裏庭に自分のお城を建てるね。
If I won the lottery, I would build my own castle in the back yard.