い adjective
あたたかい
何か温かいものが飲みたいなぁ。
I want to drink something warm.
初心者なので、どうか温かい目で見まもってください。
I'm a beginner, so please go easy on me.
「デザートに温かいアイスクリームはいかがですか？」 「いいえ、もう結構です。」
"Would you like some warm ice cream for dessert?" "No, we’re all set."
This is a single kanji with an い on the end, meaning you know it's probably an adjective. What's the adjective form of warm? It's warm.
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 that reading with this kanji, so here's a mnemonic to help you: Touch something that's warm... too warm! You pull your hand back and go "AH ta ta! (あたた). People make this noise when they touch something that's hot, I hear. It's almost like saying "hot hot hot" while dropping the "h" sound.